KubeArmor is a cloud-native runtime security enforcement system that restricts the behavior (such as process execution, file access, and networking operations) of pods, containers, and nodes (VMs) at the system level.
KubeArmor leverages Linux security modules (LSMs) such as AppArmor, SELinux, or BPF-LSM to enforce the user-specified policies. KubeArmor generates rich alerts/telemetry events with container/pod/namespace identities by leveraging eBPF.
Architecture Overview
Biweekly Meeting
KubeArmor uses Tracee's system call utility functions.
KubeArmor supports attack prevention, not just observability and monitoring. More importantly, the prevention is handled inline: even before a process is spawned, a rule can deny execution of a process. Most other systems typically employ "post-attack mitigation" that kills a process/pod after malicious intent is observed, allowing an attacker to execute code on the target environment. Essentially KubeArmor uses inline mitigation to reduce the attack surface of a pod/container/VM. KubeArmor leverages best of breed Linux Security Modules (LSMs) such as AppArmor, BPF-LSM, and SELinux (only for host protection) for inline mitigation. LSMs have several advantages over other techniques:
KubeArmor does not change anything with the pod/container.
KubeArmor does not require any changes at the host level or at the CRI (Container Runtime Interface) level to enforce blocking rules. KubeArmor deploys as a non-privileged DaemonSet with certain capabilities that allows it to monitor other pods/containers and the host.
A given cluster can have multiple nodes utilizing different LSMs. KubeArmor abstracts away complexities of LSMs and provides an easy way to enforce policies. KubeArmor manages complexity of LSMs under-the-hood.
Post-Attack Mitigation and its flaws
Post-exploit Mitigation works by killing a suspicious process in response to an alert indicating malicious intent.
Attacker is allowed to execute a binary. Attacker could disable security controls, access logs, etc to circumvent attack detection.
By the time a malicious process is killed, sensitive contents could have already been deleted, encrypted, or transmitted.
Problems with k8s native Pod Security Context
This approach has multiple problems:
It is often difficult to predict which LSM (AppArmor or SELinux) would be available on the target node.
BPF-LSM is not supported by Pod Security Context.
It is difficult to manually specify an AppArmor or SELinux policy. Changing default AppArmor or SELinux policies might result in more security holes since it is difficult to decipher the implications of the changes and can be counter-productive.
Problems with multi-cloud deployment
Different managed cloud providers use different default distributions. Google GKE COS uses AppArmor by default, AWS Bottlerocket uses BPF-LSM and SELinux, and AWS Amazon Linux 2 uses only SELinux by default. Thus it is challenging to use Pod Security Context in multi-cloud deployments.
Use of BPF-LSM
References:
Getting Started
Install KubeArmor
Install kArmor CLI (Optional)
Deploy test nginx app
[!NOTE] $POD is used to refer to the target nginx pod in many cases below.
Sample policies
Deny execution of package management tools (apt/apt-get)
Package management tools can be used in the runtime env to download new binaries that will increase the attack surface of the pods. Attackers use package management tools to download accessory tooling (such as masscan) to further their cause. It is better to block usage of package management tools in production environments.
Lets apply the policy to block such execution:
Now execute the apt command to download the masscan tool.
It will be denied permission to execute.
Get policy violations notifications using kArmor CLI
Deny access to service account token
K8s mounts the service account token by default in each pod even if there is no app using it. Attackers use these service account tokens to do lateral movements.
For e.g., to access service account token:
Thus we can see that one can use the service account token to access the Kube API server.
Lets apply a policy to block access to service account token:
Now when anyone tries to access to service account token, it would be Permission Denied.
Audit access to folders/paths
Access to certain folders/paths might have to be audited for compliance/reporting reasons.
File Visibility is disabled by default to minimize telemetry. Some file based policies will need that enabled. To enable file visibility on a namespace level:
For more details on this: https://docs.kubearmor.io/kubearmor/documentation/kubearmor_visibility#updating-namespace-visibility
Lets audit access to /etc/nginx/ folder within the deployment.
Note: karmor logs -n default would show all the audit/block operations.
Zero Trust Least Permissive Policy: Allow only nginx to execute in the pod, deny rest
Least permissive policies require one to allow certain actions/operations and deny rest. With KubeArmor it is possible to specify as part of the policy as to what actions should be allowed and deny/audit the rest.
By default the security posture is set to audit. Lets change the security posture to default deny.
Observe that the policy contains Allow action. Once there is any KubeArmor policy having Allow action then the pods enter least permissive mode, allowing only explicitly allowed operations.
Note: Use kubectl port-forward $POD --address 0.0.0.0 8080:80 to access nginx and you can see that the nginx web access still works normally.
Lets try to execute some other processes:
Any binary other than bash and nginx would be permission denied.
KubeArmor is Sandbox Project of the Cloud Native Computing Foundation.
, “post-exploitation detection/mitigation is at the mercy of an exploit writer putting little to no effort into avoiding tripping these detection mechanisms.”
allows one to specify or policies.
This guide assumes you have access to a . If you want to try non-k8s mode, for instance systemd mode to protect/audit containers or processes on VMs/bare-metal, check .
Check the to verify if your platform is supported.
You can find more details about helm related values and configurations .
[!NOTE] kArmor CLI provides a Developer Friendly way to interact with KubeArmor Telemetry. You can stream KubeArmor telemetry independently of kArmor CLI tool and integrate it with your chosen SIEM (Security Information and Event Management) solutions. on how to achieve this integration. This guide assumes you have kArmor CLI to access KubeArmor Telemetry but you can view it on your SIEM tool once integrated.
If you don't see Permission denied please refer to debug this issue
If you don't see Permission denied please refer to debug this issue.
defines what happens to the operations that are not in the allowed list. Should it be audited (allow but alert), or denied (block and alert)?
If you don't see Permission denied please refer to debug this issue
curl -sfL http://get.kubearmor.io/ | sudo sh -s -- -b /usr/local/bin
# sudo access is needed to install it in /usr/local/bin directory. But, if you prefer not to use sudo, you can install it in a different directory which is in your PATH.
Note that the above command doesn't installs the recommended packages, as we ship object files along with the package file. In case you don't have BTF, consider removing --no-install-recommends flag.
Save the above policy to hostpolicy.yaml and apply:
karmor vm policy add hostpolicy.yaml
Now if you run sleep command, the process would be denied execution.
Note that sleep may not blocked if you run it in the same terminal where you apply the above policy. In that case, please open a new terminal and run sleep again to see if the command is blocked.
KubeArmor is a security solution for the Kubernetes and cloud native platforms that helps protect your workloads from attacks and threats. It does this by providing a set of hardening policies that are based on industry-leading compliance and attack frameworks such as CIS, MITRE, NIST-800-53, and STIGs. These policies are designed to help you secure your workloads in a way that is compliant with these frameworks and recommended best practices.
One of the key features of KubeArmor is that it provides these hardening policies out-of-the-box, meaning that you don't have to spend time researching and configuring them yourself. Instead, you can simply apply the policies to your workloads and immediately start benefiting from the added security that they provide.
Additionally, KubeArmor presents these hardening policies in the context of your workload, so you can see how they will be applied and what impact they will have on your system. This allows you to make informed decisions about which policies to apply, and helps you understand the trade-offs between security and functionality.
Overall, KubeArmor is a powerful tool for securing your Kubernetes workloads, and its out-of-the-box hardening policies based on industry-leading compliance and attack frameworks make it easy to get started and ensure that your system is as secure as possible.
What is the source of these hardening policies?
Hardening policies are derived from industry leading compliance standards and attack frameworks such as CIS, MITRE, NIST, STIGs, and several others. KubeArmor Policy Templates contains the latest hardening policies. KubeArmor client tool (karmor) provides a way (karmor recommend) to fetch the policies in the context of the kubernetes workloads or specific container using command line. The output is a set of KubeArmorPolicy or KubeArmorHostPolicy that can be applied using k8s native tools (such as kubectl apply).
The rules in hardening policies are based on inputs from:
Get the hardening policies in context of all the deployment in namespace NAMESPACE:
karmor recommend -n NAMESPACE
The recommended policies would be available in the out folder.
Sample recommended hardening policies
❯ karmor recommend -n dvwa
INFO[0000] pulling image image="cytopia/dvwa:php-8.1"
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-maintenance-tool-access.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-cert-access.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-system-owner-discovery.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-system-monitoring-deny-write-under-bin-directory.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-system-monitoring-write-under-dev-directory.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-system-monitoring-detect-access-to-cronjob-files.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-least-functionality-execute-package-management-process-in-container.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-deny-remote-file-copy.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-deny-write-in-shm-folder.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-deny-write-under-etc-directory.yaml ...
created policy out/dvwa-dvwa-web/cytopia-dvwa-php-8-1-deny-write-under-etc-directory.yaml ...
INFO[0000] pulling image image="mariadb:10.1"
created policy out/dvwa-dvwa-mysql/mariadb-10-1-maintenance-tool-access.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-cert-access.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-system-owner-discovery.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-system-monitoring-deny-write-under-bin-directory.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-system-monitoring-write-under-dev-directory.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-system-monitoring-detect-access-to-cronjob-files.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-least-functionality-execute-package-management-process-in-container.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-deny-remote-file-copy.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-deny-write-in-shm-folder.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-deny-write-under-etc-directory.yaml ...
created policy out/dvwa-dvwa-mysql/mariadb-10-1-deny-write-under-etc-directory.yaml ...
output report in out/report.txt ...
Deployment | dvwa/dvwa-web
Container | cytopia/dvwa:php-8.1
OS | linux
Arch |
Distro |
Output Directory | out/dvwa-dvwa-web
policy-template version | v0.1.6
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| POLICY | SHORT DESC | SEVERITY | ACTION | TAGS |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-maintenance- | Restrict access to maintenance | 1 | Block | PCI_DSS |
| tool-access.yaml | tools (apk, mii-tool, ...) | | | MITRE |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-cert- | Restrict access to trusted | 1 | Block | MITRE |
| access.yaml | certificated bundles in the OS | | | MITRE_T1552_unsecured_credentials |
| | image | | | |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-system-owner- | System Information Discovery | 3 | Block | MITRE |
| discovery.yaml | - block system owner discovery | | | MITRE_T1082_system_information_discovery |
| | commands | | | |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-system- | System and Information | 5 | Block | NIST NIST_800-53_AU-2 |
| monitoring-deny-write-under-bin- | Integrity - System Monitoring | | | NIST_800-53_SI-4 MITRE |
| directory.yaml | make directory under /bin/ | | | MITRE_T1036_masquerading |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-system- | System and Information | 5 | Audit | NIST NIST_800-53_AU-2 |
| monitoring-write-under-dev- | Integrity - System Monitoring | | | NIST_800-53_SI-4 MITRE |
| directory.yaml | make files under /dev/ | | | MITRE_T1036_masquerading |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-system- | System and Information | 5 | Audit | NIST SI-4 |
| monitoring-detect-access-to- | Integrity - System Monitoring | | | NIST_800-53_SI-4 |
| cronjob-files.yaml | Detect access to cronjob files | | | |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-least- | System and Information | 5 | Block | NIST |
| functionality-execute-package- | Integrity - Least | | | NIST_800-53_CM-7(4) |
| management-process-in- | Functionality deny execution | | | SI-4 process |
| container.yaml | of package manager process in | | | NIST_800-53_SI-4 |
| | container | | | |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-deny-remote- | The adversary is trying to | 5 | Block | MITRE |
| file-copy.yaml | steal data. | | | MITRE_TA0008_lateral_movement |
| | | | | MITRE_TA0010_exfiltration |
| | | | | MITRE_TA0006_credential_access |
| | | | | MITRE_T1552_unsecured_credentials |
| | | | | NIST_800-53_SI-4(18) NIST |
| | | | | NIST_800-53 NIST_800-53_SC-4 |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-deny-write-in- | The adversary is trying to | 5 | Block | MITRE_execution |
| shm-folder.yaml | write under shm folder | | | MITRE |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-deny-write- | The adversary is trying to | 5 | Block | NIST_800-53_SI-7 NIST |
| under-etc-directory.yaml | avoid being detected. | | | NIST_800-53_SI-4 NIST_800-53 |
| | | | | MITRE_T1562.001_disable_or_modify_tools |
| | | | | MITRE_T1036.005_match_legitimate_name_or_location |
| | | | | MITRE_TA0003_persistence |
| | | | | MITRE MITRE_T1036_masquerading |
| | | | | MITRE_TA0005_defense_evasion |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| cytopia-dvwa-php-8-1-deny-write- | Adversaries may delete or | 5 | Block | NIST NIST_800-53 NIST_800-53_CM-5 |
| under-etc-directory.yaml | modify artifacts generated | | | NIST_800-53_AU-6(8) |
| | within systems to remove | | | MITRE_T1070_indicator_removal_on_host |
| | evidence. | | | MITRE MITRE_T1036_masquerading |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
Deployment | dvwa/dvwa-mysql
Container | mariadb:10.1
OS | linux
Arch |
Distro |
Output Directory | out/dvwa-dvwa-mysql
policy-template version | v0.1.6
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| POLICY | SHORT DESC | SEVERITY | ACTION | TAGS |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-maintenance-tool- | Restrict access to maintenance | 1 | Block | PCI_DSS |
| access.yaml | tools (apk, mii-tool, ...) | | | MITRE |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-cert-access.yaml | Restrict access to trusted | 1 | Block | MITRE |
| | certificated bundles in the OS | | | MITRE_T1552_unsecured_credentials |
| | image | | | |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-system-owner- | System Information Discovery | 3 | Block | MITRE |
| discovery.yaml | - block system owner discovery | | | MITRE_T1082_system_information_discovery |
| | commands | | | |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-system-monitoring- | System and Information | 5 | Block | NIST NIST_800-53_AU-2 |
| deny-write-under-bin-directory.yaml | Integrity - System Monitoring | | | NIST_800-53_SI-4 MITRE |
| | make directory under /bin/ | | | MITRE_T1036_masquerading |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-system-monitoring- | System and Information | 5 | Audit | NIST NIST_800-53_AU-2 |
| write-under-dev-directory.yaml | Integrity - System Monitoring | | | NIST_800-53_SI-4 MITRE |
| | make files under /dev/ | | | MITRE_T1036_masquerading |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-system-monitoring- | System and Information | 5 | Audit | NIST SI-4 |
| detect-access-to-cronjob-files.yaml | Integrity - System Monitoring | | | NIST_800-53_SI-4 |
| | Detect access to cronjob files | | | |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-least-functionality- | System and Information | 5 | Block | NIST |
| execute-package-management-process- | Integrity - Least | | | NIST_800-53_CM-7(4) |
| in-container.yaml | Functionality deny execution | | | SI-4 process |
| | of package manager process in | | | NIST_800-53_SI-4 |
| | container | | | |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-deny-remote-file- | The adversary is trying to | 5 | Block | MITRE |
| copy.yaml | steal data. | | | MITRE_TA0008_lateral_movement |
| | | | | MITRE_TA0010_exfiltration |
| | | | | MITRE_TA0006_credential_access |
| | | | | MITRE_T1552_unsecured_credentials |
| | | | | NIST_800-53_SI-4(18) NIST |
| | | | | NIST_800-53 NIST_800-53_SC-4 |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-deny-write-in-shm- | The adversary is trying to | 5 | Block | MITRE_execution |
| folder.yaml | write under shm folder | | | MITRE |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-deny-write-under-etc- | The adversary is trying to | 5 | Block | NIST_800-53_SI-7 NIST |
| directory.yaml | avoid being detected. | | | NIST_800-53_SI-4 NIST_800-53 |
| | | | | MITRE_T1562.001_disable_or_modify_tools |
| | | | | MITRE_T1036.005_match_legitimate_name_or_location |
| | | | | MITRE_TA0003_persistence |
| | | | | MITRE MITRE_T1036_masquerading |
| | | | | MITRE_TA0005_defense_evasion |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
| mariadb-10-1-deny-write-under-etc- | Adversaries may delete or | 5 | Block | NIST NIST_800-53 NIST_800-53_CM-5 |
| directory.yaml | modify artifacts generated | | | NIST_800-53_AU-6(8) |
| | within systems to remove | | | MITRE_T1070_indicator_removal_on_host |
| | evidence. | | | MITRE MITRE_T1036_masquerading |
+-------------------------------------+--------------------------------+----------+--------+---------------------------------------------------+
Key highlights:
The hardening policies are available by default in the out folder separated out in directories based on deployment names.
Get an HTML report by using the option --report report.html with karmor recommend.
Get hardening policies in context to specific compliance by specifying --tag <CIS/MITRE/...> option.
Support Matrix
KubeArmor supports following types of workloads:
K8s orchestrated: Workloads deployed as k8s orchestrated containers. In this case, Kubearmor is deployed as a k8s daemonset. Note, KubeArmor supports policy enforcement on both k8s-pods (KubeArmorPolicy) as well as k8s-nodes (KubeArmorHostPolicy).
Containerized: Workloads that are containerized but not k8s orchestrated are supported. KubeArmor installed in systemd mode can be used to protect such workloads.
VM/Bare-Metals: Workloads deployed on Virtual Machines or Bare Metal i.e. workloads directly operating as host/system processes. In this case, Kubearmor is deployed in systemd mode.
Kubernetes Support Matrix
Supported Linux Distributions
Following distributions are tested for VM/Bare-metal based installations:
Note Full: Supports both enforcement and observability
Partial: Supports only observability
Platform I am interested is not listed here! What can I do?
Please approach the Kubearmor community on slack or raise a GitHub issue to express interest in adding the support.
It would be very much appreciated if you can test kubearmor on a platform not listed above and if you have access to. Once tested you can update this document and raise a PR.
Least Permissive Access
KubeArmor helps organizations enforce a zero trust posture within their Kubernetes clusters. It allows users to define an allow-based policy that allows specific operations, and denies or audits all other operations. This helps to ensure that only authorized activities are allowed within the cluster, and that any deviations from the expected behavior are denied and flagged for further investigation.
By implementing a zero trust posture with KubeArmor, organizations can increase their security posture and reduce the risk of unauthorized access or activity within their Kubernetes clusters. This can help to protect sensitive data, prevent system breaches, and maintain the integrity of the cluster.
Allow execution of only specific processes within the pod
Observe that the policy contains Allow action. Once there is any KubeArmor policy having Allow action then the pods enter least permissive mode, allowing only explicitly allowed operations.
Note: Use kubectl port-forward $POD --address 0.0.0.0 8080:80 to access nginx and you can see that the nginx web access still works normally.
Lets try to execute some other processes:
This would be permission denied.
Challenges with maintaining Zero Trust Security Posture
Achieving Zero Trust Security Posture is difficult. However, the more difficult part is to maintain the Zero Trust posture across application updates. There is also a risk of application downtime if the security posture is not correctly identified. While KubeArmor provides a way to enforce Zero Trust Security Posture, identifying the policies/rules for achieving this is non-trivial and requires that you keep the policies in dry-run mode (or default audit mode) before using the default-deny mode.
Application Behavior
KubeArmor has visibility into systems and application behavior. KubeArmor summarizes/aggregates the information and provides a user-friendly view to figure out the application behavior.
What application behavior is shown?
Process data:
What are the processes executing in the pods?
What processes are executing through which parent processes?
File data:
What are the file system accesses made by different processes?
Network Accesses:
What are the Ingress/Egress connections from the pod?
What server binds are done in the pod?
How to get the application behavior?
Get visibility into process executions in default namespace.
KubeArmor supports allow-based policies which results in specific actions to be allowed and denying/auditing everything else. For example, a specific pod/container might only invoke a set of binaries at runtime. As part of allow-based rules you can specify the set of processes that are allowed and everything else is either audited or denied based on the .
KubeArmor provides framework so as to smoothen the journey to Zero Trust posture. For e.g., it is possible to set dry-run/audit mode at the namespace level by . Thus, you can have different namespaces in different default security posture modes (default-deny vs default-audit). Users can switch to default-deny mode once they are comfortable (i.e., they do not see any alerts) with the settings.
Now we can get general telemetry events in the context of the host using karmor logs .The logs related to Host Visibility will have type Type: HostLogand Operation: File | Process | Network
The logs can also be generated in JSON format using karmor logs --logFilter=all --json
Updating Namespace Visibility
KubeArmor has the ability to let the user select what kind of events have to be traced by changing the annotation kubearmor-visibility at the namespace.
Checking Namespace visibility
Namespace visibility can be checked using kubectl describe.
To update the visibility of namespace : Now let's update Kubearmor visibility using kubectl annotate. Currently KubeArmor supports process, file, network, capabilities. Lets try to update visibility for the namespace wordpress-mysql
Note: To turn off the visibility across all aspects, use kubearmor-visibility=none. Note that any policy violations or events that results in non-success returns would still be reported in the logs.
Open up a terminal, and watch logs using the karmor cli
karmor logs --logFilter=all -n wordpress-mysql
In another terminal, let's exec into the pod and run some process commands . Try ls inside the pod
POD_NAME=$(kubectl get pods -n wordpress-mysql -l app=wordpress -o jsonpath='{.items[0].metadata.name}') && kubectl -n wordpress-mysql exec -it $POD_NAME -- bash
# ls
Now, we can notice that no logs have been generated for the above command and logs with only Operation: Network are shown.
Note If telemetry is disabled, the user wont get audit event even if there is an audit rule.
Note Only the logs are affected by changing the visibility, we still get all the alerts that are generated.
Let's simulate a sample policy violation, and see whether we still get alerts or not.
Container alerts are generated when there is a policy violation or audit event that is raised due to a policy action. For example, a policy might block execution of a process. When the execution is blocked by KubeArmor enforcer, KubeArmor generates an alert event implying policy action. In the case of an Audit action, the KubeArmor will only generate an alert without actually blocking the action.
The primary difference in the container alerts events vs the telemetry events (showcased above) is that the alert events contains certain additional fields such as policy name because of which the alert was generated and other metadata such as "Tags", "Message", "Severity" associated with the policy rule.
Container Alerts Fields format
Process Alert
{"ClusterName":"default","HostName":"aks-agentpool-16128849-vmss000001","NamespaceName":"wordpress-mysql","PodName":"wordpress-787f45786f-2q9wf","Labels":"app=wordpress","ContainerID":"72de193fc8d849cd052affae5a53a27111bcefb75385635dcb374acdf31a5548","ContainerName":"wordpress", "ContainerImage": "docker.io/library/wordpress:4.8-apache@sha256:6216f64ab88fc51d311e38c7f69ca3f9aaba621492b4f1fa93ddf63093768845",
"HostPPID":495804,"HostPID":495877,"PPID":309835,"PID":309841,"ParentProcessName":"/bin/bash","ProcessName":"/usr/bin/apt","PolicyName":"harden-wordpress-pkg-mngr-exec","Severity":"5","Tags":"NIST,NIST_800-53_CM-7(4),SI-4,process,NIST_800-53_SI-4","ATags": ["NIST","NIST_800-53_CM-7(4)","SI-4","process","NIST_800-53_SI-4" ],"Message":"Alert! Execution of package management process inside container is denied","Type":"MatchedPolicy","Source":"/bin/bash","Operation":"Process","Resource":"/usr/bin/apt","Data":"syscall=SYS_EXECVE","Enforcer":"AppArmor","Action":"Block","Result":"Permission denied"}
File Alert
{"ClusterName":"default","HostName":"aks-agentpool-16128849-vmss000001","NamespaceName":"wordpress-mysql","PodName":"wordpress-787f45786f-2q9wf","Labels":"app=wordpress","ContainerID":"72de193fc8d849cd052affae5a53a27111bcefb75385635dcb374acdf31a5548","ContainerName":"wordpress", "ContainerImage": "docker.io/library/wordpress:4.8-apache@sha256:6216f64ab88fc51d311e38c7f69ca3f9aaba621492b4f1fa93ddf63093768845",
"HostPPID":495804,"HostPID":496390,"PPID":309835,"PID":309842,"ParentProcessName":"/bin/bash","ProcessName":"/bin/rm","PolicyName":"harden-wordpress-file-integrity-monitoring","Severity":"1","Tags":"NIST,NIST_800-53_AU-2,NIST_800-53_SI-4,MITRE,MITRE_T1036_masquerading,MITRE_T1565_data_manipulation","ATags": ["NIST","NIST_800-53_AU-2","NIST_800-53_SI-4","MITRE","MITRE_T1036_masquerading","MITRE_T1565_data_manipulation" ],"Message":"Detected and prevented compromise to File integrity","Type":"MatchedPolicy","Source":"/bin/rm /sbin/raw","Operation":"File","Resource":"/sbin/raw","Data":"syscall=SYS_UNLINKAT flags=","Enforcer":"AppArmor","Action":"Block","Result":"Permission denied"}
Note that KubeArmor also alerts events blocked due to other system policy enforcement. For example, if an SELinux native rule blocks an action, KubeArmor will report those as well as DefaultPosture events. Following is an example of such event:
{"Timestamp":1692814089,"UpdatedTime":"2023-08-23T18:08:09.522743Z","ClusterName":"default","HostName":"gke-my-first-cluster-1-default-pool-9144db50-81gb","HostPPID":1791315,"HostPID":1791316,"PPID":1791315,"PID":1791316,"UID":204,"ParentProcessName":"/usr/sbin/sshd","ProcessName":"/usr/sbin/sshd","PolicyName":"DefaultPosture","Type":"MatchedHostPolicy","Source":"/usr/sbin/sshd","Operation":"Syscall","Data":"syscall=SYS_SETGID userid=0","Enforcer":"BPFLSM","Action":"Block","Result":"Operation not permitted"}
Blocked SETUID
Note that KubeArmor also alerts events blocked due to other system policy enforcement. For example, if an SELinux native rule blocks an action, KubeArmor will report those as well as DefaultPosture events. Following is an example of such event:
{"Timestamp":1692814089,"UpdatedTime":"2023-08-23T18:08:09.523964Z","ClusterName":"default","HostName":"gke-my-first-cluster-1-default-pool-9144db50-81gb","HostPPID":1791315,"HostPID":1791316,"PPID":1791315,"PID":1791316,"UID":204,"ParentProcessName":"/usr/sbin/sshd","ProcessName":"/usr/sbin/sshd","PolicyName":"DefaultPosture","Type":"MatchedHostPolicy","Source":"/usr/sbin/sshd","Operation":"Syscall","Data":"syscall=SYS_SETUID userid=0","Enforcer":"BPFLSM","Action":"Block","Result":"Operation not permitted"}
Policy Examples for Containers
Here, we demonstrate how to define security policies using our example microservice (multiubuntu).
Process Execution Restriction
Explanation: The purpose of this policy is to block the execution of '/bin/sleep' in the containers with the 'group-1' label. For this, we define the 'group-1' label in selector -> matchLabels and the specific path ('/bin/sleep') in process -> matchPaths. Also, we put 'Block' as the action of this policy.
Verification: After applying this policy, please get into one of the containers with the 'group-1' (using "kubectl -n multiubuntu exec -it ubuntu-X-deployment-... -- bash") and run '/bin/sleep'. You will see that /bin/sleep is blocked.
Explanation: The purpose of this policy is to block all executables in the '/sbin' directory. Since we want to block all executables rather than a specific executable, we use matchDirectories to specify the executables in the '/sbin' directory at once.
Verification: After applying this policy, please get into the container with the 'ubuntu-1' label and run '/sbin/route' to see if this command is allowed (this command will be blocked).
Explanation: As the extension of the previous policy, we want to block all executables in the '/usr' directory and its subdirectories (e.g., '/usr/bin', '/usr/sbin', and '/usr/local/bin'). Thus, we add 'recursive: true' to extend the scope of the policy.
Verification: After applying this policy, please get into the container with the 'ubuntu-2' label and run '/usr/bin/env' or '/usr/bin/whoami'. You will see that those commands are blocked.
Explanation: Here, we want the container with the 'ubuntu-3' label only to access certain files by specific executables. Otherwise, we want to block any other file accesses. To achieve this goal, we define the scope of this policy using matchDirectories with fromSource and use the 'Allow' action.
Verification: In this policy, we allow /bin/cat to access the files in /credentials only. After applying this policy, please get into the container with the 'ubuntu-3' label and run 'cat /credentials/password'. This command will be allowed with no errors. Now, please run 'cat /etc/hostname'. Then, this command will be blocked since /bin/cat is only allowed to access /credentials/*.
Explanation: This policy aims to allow a specific user (i.e., user1) only to launch its own executable (i.e., hello), which means that we do not want for the root user to even launch /home/user1/hello. For this, we define a security policy with matchPaths and 'ownerOnly: ture'.
Verification: For verification, we also allow several directories and files to change users (from 'root' to 'user1') in the policy. After applying this policy, please get into the container with the 'ubuntu-3' label and run '/home/user1/hello' first. This command will be blocked even though you are the 'root' user. Then, please run 'su - user1'. Now, you are the 'user1' user. Please run '/home/user1/hello' again. You will see that it works now.
File Access Restriction
Explanation: The purpose of this policy is to allow the container with the 'ubuntu-4' label to read '/credentials/password' only (the write operation is blocked).
Verification: After applying this policy, please get into the container with the 'ubuntu-4' label and run 'cat /credentials/password'. You can see the contents in the file. Now, please run 'echo "test" >> /credentials/password'. You will see that the write operation will be blocked.
Explanation: In this policy, we do not want the container with the 'ubuntu-5' label to access any files in the '/credentials' directory and its subdirectories. Thus, we use 'matchDirectories' and 'recursive: true' to define all files in the '/credentials' directory and its subdirectories.
Verification: After applying this policy, please get into the container with the 'ubuntu-5' label and run 'cat /secret.txt'. You will see the contents of /secret.txt. Then, please run 'cat /credentials/password'. This command will be blocked due to the security policy.
Network Operation Restriction
Explanation: We want to audit sending ICMP packets from the containers with the 'ubuntu-5' label while allowing packets for the other protocols (e.g., TCP and UDP). For this, we use 'matchProtocols' to define the protocol (i.e., ICMP) that we want to block.
Verification: After applying this policy, please get into the container with the 'ubuntu-5' label and run 'curl https://kubernetes.io/'. This will work fine. Then, run 'ping 8.8.8.8'. You will see 'Permission denied' since the 'ping' command internally uses the ICMP protocol.
Capabilities Restriction
Explanation: We want to block any network operations using raw sockets from the containers with the 'ubuntu-1' label, meaning that containers cannot send non-TCP/UDP packets (e.g., ICMP echo request or reply) to other containers. To achieve this, we use matchCapabilities and specify the 'CAP_NET_RAW' capability to block raw socket creations inside the containers. Here, since we use the stream and datagram sockets to TCP and UDP packets respectively, we can still send those packets to others.
Verification: After applying this policy, please get into the container with the 'ubuntu-1' label and run 'curl https://kubernetes.io/'. This will work fine. Then, run 'ping 8.8.8.8'. You will see 'Operation not permitted' since the 'ping' command internally requires a raw socket to send ICMP packets.
System calls alerting
Alert for all unlink syscalls
Generated telemetry
Alert on all rmdir syscalls targeting anything in /home/ directory and sub-directories
Generated telemetry
Security Posture
There are two default mode of operations available block and audit. block mode blocks all the operations that are not allowed in the policy. audit generates telemetry events for operations that would have been blocked otherwise.
KubeArmor has 4 types of resources: Process, File, Network and Capabilities. Default Posture is configurable for each of the resources seperately except Process. Process based operations are treated under File resource only.
Configuring Default Posture
Global Default Posture
Note By default, KubeArmor set the Global default posture to audit
Global default posture is configured using configuration options passed to KubeArmor using configuration file
Or using command line flags with the KubeArmor binary
Namespace Default Posture
We use namespace annotations to configure default posture per namespace. Supported annotations keys are kubearmor-file-posture,kubearmor-network-posture and kubearmor-capabilities-posture with values block or audit. If a namespace is annotated with a supported key and an invalid value ( like kubearmor-file-posture=invalid), KubeArmor will update the value with the global default posture ( i.e. to kubearmor-file-posture=block).
Example
Let's start KubeArmor with configuring default network posture to audit in the following YAML.
Contents of kubearmor.yaml
Here's a sample policy to allow tcp connections from curl binary.
Inside the ubuntu-5-deployment, if we try to access tcp using curl. It works as expected with no telemetry generated.
If we try to access udp using curl, a bunch of telemetry is generated for the udp access.
curl google.com requires UDP for DNS resolution.
Generated alert has Policy Name DefaultPosture and Action as Audit
Now let's update the default network posture to block for multiubuntu namespace.
Now if we try to access udp using curl, the action is blocked and related alerts are generated.
Here curl couldn't resolve google.com due to blocked access to UDP.
Generated alert has Policy Name DefaultPosture and Action as Block
Let's try to set the annotation value to something invalid.
We can see that, annotation value was automatically updated to audit since that was global mode of operation for network in the KubeArmor configuration.
Policy Spec for Containers
Policy Specification
Here is the specification of a security policy.
Note Please note that for system calls monitoring we only support audit action no matter what the value of action is
Policy Spec Description
Now, we will briefly explain how to define a security policy.
Common
A security policy starts with the base information such as apiVersion, kind, and metadata. The apiVersion and kind would be the same in any security policies. In the case of metadata, you need to specify the names of a policy and a namespace where you want to apply the policy.
Severity
The severity part is somewhat important. You can specify the severity of a given policy from 1 to 10. This severity will appear in alerts when policy violations happen.
Tags
The tags part is optional. You can define multiple tags (e.g., WARNING, SENSITIVE, MITRE, STIG, etc.) to categorize security policies.
Message
The message part is optional. You can add an alert message, and then the message will be presented in alert logs.
Selector
The selector part is relatively straightforward. Similar to other Kubernetes configurations, you can specify (a group of) pods based on labels.
If this is enabled, the owners of the executable(s) defined with matchPaths and matchDirectories will be only allowed to execute.
recursive
If this is enabled, the coverage will extend to the subdirectories of the directory defined with matchDirectories.
fromSource
If a path is specified in fromSource, the executable at the path will be allowed/blocked to execute the executables defined with matchPaths or matchDirectories. For better understanding, let us say that an operator defines a policy as follows. Then, /bin/bash will be only allowed (blocked) to execute /bin/sleep. Otherwise, the execution of /bin/sleep will be blocked (allowed).
File
The file section is quite similar to the process section.
The only difference between 'process' and 'file' is the readOnly option.
readOnly (static action: allow to read only; otherwise block all)
If this is enabled, the read operation will be only allowed, and any other operations (e.g., write) will be blocked.
Network
In the case of network, there is currently one match type: matchProtocols. You can define specific protocols among TCP, UDP, and ICMP.
Capabilities
Syscalls
In the case of syscalls, there are two types of matches, matchSyscalls and matchPaths. matchPaths can be used to target system calls targeting specific binary path or anything under a specific directory, additionally you can slice based on syscalls generated by a binary or a group of binaries in a directory. You can use matchSyscall as a more general rule to match syscalls from all sources or from specific binaries.
There is one options in each match.
fromSource
If a path is specified in fromSource, kubearmor will match only syscalls generated by the defined source. For better undrestanding, lets take the example below. Only unlink system calls generated by /bin/bash will be matched.
recursive
If this is enabled, the coverage will extend to the subdirectories of the directory.
Action
Advanced
Service Account token: Protect access to k8s service account token
Description
K8s mounts the service account token as part of every pod by default. The service account token is a credential that can be used as a bearer token to access k8s APIs and gain access to other k8s entities. Many times there are no processes in the pod that use the service account tokens which means in such cases the k8s service account token is an unused asset that can be leveraged by the attacker.
Attack Scenario
It's important to note that attackers often look for ways to gain access to other entities within Kubernetes clusters. One common method is to check for credential accesses, such as service account tokens, in order to perform lateral movements. For instance, in many Kubernetes attacks, once the attacker gains entry into a pod, they may attempt to use a service account token to access other entities.
Attack type Credential Access, Comand Injection
Actual Attack Hildegard, BlackT, BlackCat RaaS
Compliance
CIS_Kubernetes_Benchmark_v1.27, Control-Id-5.1.6
Policy
Service account token
Simulation
Expected Alert
References
FIM: File Integrity Monitoring/Protection
Description
Changes to system binary folders, configuration paths, and credentials paths need to be monitored for change. With KubeArmor, one can not only monitor for changes but also block any write attempts in such system folders. Compliance frameworks such as PCI-DSS, NIST, and CIS expect FIM to be in place.
Attack Scenario
In a possible attack scenario, an attacker may try to update the configuration to disable security controls or access logs. This can allow them to gain further access to the system and carry out malicious activities undetected. It's crucial to be aware of such threats and take proactive measures to prevent such attacks from occurring.
Attack Type Data Manipulation, Integrity Threats
Actual Attack NetWalker, Conti, DarkSide RaaS
Compliance
CIS Distribution Independent Linuxv2.0, Control-Id:6.3.5
PCI-DSS, Requirement: 6
PCI-DSS, Requirement: 10
NIST_800-53_AU-2
MITRE_T1565_data_manipulation
Policy
File Integrity Monitoring
Simulation
Expected Alert
References
Packaging tools: Deny execution of package management tools
Description
Pods/Containers might get shipped with binaries which should never used in the production environments. Some of those bins might be useful in dev/staging environments but the same container image is carried forward in most cases to the production environment too. For security reasons, the devsecops team might want to disable the use of these binaries in the production environment even though the bins exists in the container. As an example, most of the container images are shipped with package management tools such as apk, apt, yum, etc. If anyone ends up using these bins in the prod env, it will increase the attack surface of the container/pod.
Attack Scenario
In an attack scenario, adversaries may use system tools such as fsck, ip, who, apt, and others for reconnaissance and to download additional tooling from remote servers. These tools can help them gain valuable information about the system and its vulnerabilities, allowing them to carry out further attacks. It's important to be vigilant about such activities and implement security measures to prevent such attacks from happening.
Attack Type Command Injection, Malware, Backdoor
Actual Attack AppleJeus, Codecov supply chain
Compliance
CIS Distribution Independent Linuxv2.0
Control-Id:6.4.5
NIST_800-53_SI-4
NIST_800-53_CM-7(4)
Policy
Packaging tools execution
Simulation
Expected Alert
References
Trusted certs bundle: Protect write access to the trusted root certificates bundle
Description
Adversaries may install a root certificate on a compromised system to avoid warnings when connecting to adversary-controlled web servers. Root certificates are used in public key cryptography to identify a root certificate authority (CA). When a root certificate is installed, the system or application will trust certificates in the root's chain of trust that have been signed by the root certificate. Installation of a root certificate on a compromised system would give an adversary a way to degrade the security of that system.
Attack Scenario
By using this technique, attackers can successfully evade security warnings that alert users when compromised systems connect over HTTPS to adversary-controlled web servers. These servers often look like legitimate websites, and are designed to trick users into entering their login credentials, which can then be used by the attackers. It's important to be aware of this threat and take necessary precautions to prevent these attacks from happening.
Attack Type Man-In-The-Middle(MITM)
Actual Attack POODLE(Padding Oracle On Downgraded Legacy Encryption), BEAST (Browser Exploit Against SSL/TLS)
Compliance
CIS Distribution Independent Linuxv2.0
Control-Id: 6.3.4
MITRE_T1552_unsecured_credentials
Policy
Trusted Certs Bundle
Simulation
Expected Alert
References
Database access: Protect read/write access to raw database tables from unknown processes.
Description
Applications use databases to store all the information such as posts, blogs, user information, etc. WordPress applications almost certainly use a MySQL database for storing their content, and those are usually stored elsewhere on the system, often /var/lib/mysql/some_db_name.
Attack Scenario
Adversaries have been known to use various techniques to steal information from databases. This information can include user credentials, posts, blogs, and more. By obtaining this information, adversaries can gain access to user accounts and potentially perform a full-account takeover, which can lead to further compromise of the target system. It's important to ensure that appropriate security measures are in place to protect against these types of attacks.
Attack Type SQL Injection, Credential Access, Account Takeover
Actual Attack Yahoo Voices Data Breach in 2012
Compliance
CIS Distribution Independent Linuxv2.0
Control-Id: 6.14.4
Policy
Database Access
Simulation
Expected Alert
References
Config data: Protect access to configuration data containing plain text credentials.
Description
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials. These can be files created by users to store their own credentials, shared credential stores for a group of individuals, configuration files containing passwords for a system or service, or source code/binary files containing embedded passwords.
Attack Scenario
In a possible attack scenario, an attacker may try to change the configurations to open websites to application security holes such as session hijacking and cross-site scripting attacks, which can lead to the disclosure of private data. Additionally, attackers can also leverage these changes to gather sensitive information. It's crucial to take proactive measures to prevent these attacks from occurring.
Attack Type Cross-Site Scripting(XSS), Data manipulation, Session hijacking
Actual Attack XSS attack on Fortnite 2019, Turla LightNeuron Attack
Compliance
CIS Distribution Independent Linuxv2.0
Control-Id: 6.16.14
Policy
Config data
Simulation
With a shell different than the user owning the file:
Expected Alert
References
File Copy: Prevent file copy using standard utilities.
Description
Exfiltration consists of techniques that adversaries may use to steal data from your network. Once they’ve collected data, adversaries often package it to avoid detection while removing it. This can include compression and encryption. Techniques for getting data out of a target network typically include transferring it over their command and control channel or an alternate channel and may also include putting size limits on the transmission.
Attack Scenario
It's important to note that file copy tools can be leveraged by attackers for exfiltrating sensitive data and transferring malicious payloads into the workloads. Additionally, it can also assist in lateral movement within the system. It's crucial to take proactive measures to prevent these attacks from occurring.
Attack Type Credential Access, Lateral movements, Information Disclosure
Actual Attack DarkBeam Data Breach, Shields Health Care Group data breach
Compliance
MITRE_TA0010_exfiltration
NIST_800-53_SI-4(18)
MITRE_TA0008_lateral_movement
Policy
File Copy
Simulation
Expected Alert
References
Network Access: Process based network access control
Description
Typically, within a pod/container, there are only specific processes that need to use network access. KubeArmor allows one to specify the set of binaries that are allowed to use network primitives such as TCP, UDP, and Raw sockets and deny everyone else.
Attack Scenario
In a possible attack scenario, an attacker binary may attempt to send a beacon to its Command and Control (C&C) Server. Additionally, the binary may use network primitives to exfiltrate pod/container data and configuration. It's important to monitor network traffic and take proactive measures to prevent these attacks from occurring, such as implementing proper access controls and segmenting the network.
Attack Type Denial of Service(DoS), Distributed Denial of Service(DDoS)
Actual Attack DDoS attacks on websites of public institutions in Belgium, DDoS attack on the website of a city government in Germany
Compliance
Network Access
Policy
Network Access
Simulation
Set the default security posture to default-deny
Expected Alert
/tmp/ noexec: Do not allow execution of binaries from /tmp/ folder.
Description
If provided the necessary privileges, users have the ability to install software in organizational information systems. To maintain control over the types of software installed, organizations identify permitted and prohibited actions regarding software installation. Prohibited software installations may include, for example, software with unknown or suspect pedigrees or software that organizations consider potentially malicious.
Attack Scenario
In an attack scenario, a hacker may attempt to inject malicious scripts into the /tmp folder through a web application exploit. Once the script is uploaded, the attacker may try to execute it on the server in order to take it down. By hardening the /tmp folder, the attacker will not be able to execute the script, preventing such attacks. It's essential to implement these security measures to protect against these types of attacks and ensure the safety of the system.
Attack Type System Failure, System Breach
Actual Attack Shields Health Care Group data breach, MOVEit Breach
Compliance
CIS Distribution Independent Linuxv2.0
Control-Id: 1.1.5
Control-Id: 1.1.10
Policy
/tmp/ noexec
Simulation
Expected Alert
References
Admin tools: Do not allow execution of administrative/maintenance tools inside the pods.
Description
Adversaries may abuse a container administration service to execute commands within a container. A container administration service such as the Docker daemon, the Kubernetes API server, or the kubelet may allow remote management of containers within an environment.
Attack Scenario
It's important to note that attackers with permissions could potentially run 'kubectl exec' to execute malicious code and compromise resources within a cluster. It's crucial to monitor the activity within the cluster and take proactive measures to prevent these attacks from occurring.
Attack Type Command Injection, Lateral Movements, etc.
Actual Attack Target cyberattack, Supply Chain Attacks
Compliance
NIST_800-53_AU-2
MITRE_T1609_container_administration_command
NIST_800-53_SI-4
Policy
Admin tools
Simulation
Expected Alert
References
Discovery tools: Do not allow discovery/search of tools/configuration.
Description
Adversaries may attempt to get a listing of services running on remote hosts and local network infrastructure devices, including those that may be vulnerable to remote software exploitation. Common methods to acquire this information include port and/or vulnerability scans using tools that are brought onto a system
Attack Scenario
Adversaries can potentially use information related to services, remote hosts, and local network infrastructure devices, including those that may be vulnerable to remote software exploitation to perform malicious attacks like exploiting open ports and injecting payloads to get remote shells. It's crucial to take proactive measures to prevent these attacks from occurring, such as implementing proper network segmentation and hardening network devices.
Attack Type Reconnaissance, Brute force, Command Injection
Actual Attack Microsoft exchange server attack 2021
Compliance
CIS Distribution Independent Linuxv2.0
Control-Id: 6.3
Policy
Discovery tools
Simulation
Expected Alert
References
Logs delete: Do not allow external tooling to delete logs/traces of critical components.
Description
Adversaries may delete or modify artifacts generated within systems to remove evidence of their presence or hinder defenses. Various artifacts may be created by an adversary or something that can be attributed to an adversary’s actions. Typically these artifacts are used as defensive indicators related to monitored events, such as strings from downloaded files, logs that are generated from user actions, and other data analyzed by defenders. Location, format, and type of artifact (such as command or login history) are often specific to each platform.
Attack Scenario
It's important to note that removal of indicators related to intrusion activity may interfere with event collection, reporting, or other processes used to detect such activity. This can compromise the integrity of security solutions by causing notable events to go unreported. Additionally, this activity may impede forensic analysis and incident response, due to a lack of sufficient data to determine what occurred. It's crucial to ensure that all relevant indicators are properly monitored and reported to prevent such issues from occurring.
Attack Type Integrity Threats, Data Manipulation Actual Attack NetWalker, Conti, DarkSide RaaS
Compliance
CIS Distribution Independent Linuxv2.0
Control-Id: 6.6
Control-Id: 7.6.2
Control-Id: 7.6.3
NIST_800-53_CM-5
Policy
Logs delete
Simulation
Expected Alert
References
ICMP control: Do not allow scanning tools to use ICMP for scanning the network.
Description
The Internet Control Message Protocol (ICMP) allows Internet hosts to notify each other of errors and allows diagnostics and troubleshooting for system administrators. Because ICMP can also be used by a potential adversary to perform reconnaissance against a target network, and due to historical denial-of-service bugs in broken implementations of ICMP, some network administrators block all ICMP traffic as a network hardening measure
Attack Scenario
Adversaries may use scanning tools that utilize Internet Control Message Protocol (ICMP) to perform reconnaissance against a target network and identify potential loopholes. It's crucial to monitor network traffic and take proactive measures to prevent these attacks from occurring, such as implementing proper firewall rules and network segmentation. Additionally, it's important to stay up-to-date with the latest security patches to prevent known vulnerabilities from being exploited.
Attack Type Network Flood, DoS(Denial of Service)
Actual Attack Ping of Death(PoD)
Compliance
ICMP Control
Policy
ICMP Control
Simulation
Expected Alert
Restrict Capabilities: Do not allow capabilities that can be leveraged by the attacker.
Description
Containers run with a default set of capabilities as assigned by the Container Runtime. Capabilities are parts of the rights generally granted on a Linux system to the root user. In many cases applications running in containers do not require any capabilities to operate, so from the perspective of the principal of least privilege use of capabilities should be minimized.
Attack Scenario
Kubernetes by default connects all the containers running in the same node (even if they belong to different namespaces) down to Layer 2 (ethernet). Every pod running in the same node is going to be able to communicate with any other pod in the same node (independently of the namespace) at ethernet level (layer 2). This allows a malicious containers to perform an ARP spoofing attack to the containers on the same node and capture their traffic.
Attack Type Reconnaissance, Spoofing
Actual Attack Recon through P.A.S. Webshell, NBTscan
Compliance
CIS Kubernetes
Control Id: 5.2.8 - Minimize the admission of containers with the NET_RAW capability
Control Id: 5.2.9 - Minimize the admission of containers with capabilities assigned
Policy
Restrict Capabilities
Simulation
Expected Alert
References
Log field
Description
Example
Alert Field
Description
Example
Block a specific executable ()
Block all executables in a specific directory ()
Block all executables in a specific directory and its subdirectories ()
Allow specific executables to access certain files only ()
Allow a specific executable to be launched by its owner only ()
Allow accessing specific files only ()
Block all file accesses in a specific directory and its subdirectories ()
Audit ICMP packets ()
Block Raw Sockets (i.e., non-TCP/UDP packets) ()
KubeArmor supports configurable default security posture. The security posture could be allow/audit/deny. Default Posture is used when there's atleast one Allow policy for the given deployment i.e. KubeArmor is handling policies in whitelisting manner (more about this in ).
Note: This example is in the environment.
For better understanding, you can check .
In the process section, there are three types of matches: matchPaths, matchDirectories, and matchPatterns. You can define specific executables using matchPaths or all executables in specific directories using matchDirectories. In the case of matchPatterns, advanced operators may be able to determine particular patterns for executables by using regular expressions. However, the coverage of regular expressions is highly dependent on AppArmor (). Thus, we generally do not recommend using this match.
In the case of capabilities, there is currently one match type: matchCapabilities. You can define specific capability names to allow or block using matchCapabilities. You can check available capabilities in .
The action could be Allow, Audit, or Block. Security policies would be handled in a blacklist manner or a whitelist manner according to the action. Thus, you need to define the action carefully. You can refer to for more details. In the case of the Audit action, we can use this action for policy verification before applying a security policy with the Block action. For System calls monitoring, we only support audit mode no matter what the action is set to.
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ClusterName
gives information about the cluster for which the log was generated
default
Operation
gives details about what type of operation happened in the pod
File/Process/ Network
ContainerID
information about the container ID from where log was generated
7aca8d52d35ab7872df6a454ca32339386be
ContainerImage
shows the image that was used to spin up the container
apiVersion:security.kubearmor.com/v1kind:KubeArmorPolicymetadata:name:ksp-ubuntu-3-proc-path-owner-allownamespace:multiubuntuspec:severity:7selector:matchLabels:container:ubuntu-3process:matchPaths: - path:/home/user1/helloownerOnly:truematchDirectories: - dir:/bin/# required to change root to user1recursive:true - dir:/usr/bin/# used in changing accountsrecursive:truefile:matchPaths: - path:/root/.bashrc# used by root - path:/root/.bash_history# used by root - path:/home/user1/.profile# used by user1 - path:/home/user1/.bashrc# used by user1 - path:/run/utmp# required to change root to user1 - path:/dev/ttymatchDirectories: - dir:/etc/# required to change root to user1 (coarse-grained way)recursive:true - dir:/proc/# required to change root to user1 (coarse-grained way)recursive:trueaction:Allow
apiVersion:security.kubearmor.com/v1kind:KubeArmorPolicymetadata:name:ksp-ubuntu-4-file-path-readonly-allownamespace:multiubuntuspec:severity:10message:"a critical file was accessed"tags: - WARNINGselector:matchLabels:container:ubuntu-4process:matchDirectories: - dir:/bin/# used by rootrecursive:true - dir:/usr/bin/# used by rootrecursive:truefile:matchPaths: - path:/credentials/passwordreadOnly:true - path:/root/.bashrc# used by root - path:/root/.bash_history# used by root - path:/dev/ttymatchDirectories: - dir:/etc/# used by root (coarse-grained way)recursive:true - dir:/proc/# used by root (coarse-grained way)recursive:trueaction:Allow
apiVersion:security.kubearmor.com/v1kind:KubeArmorPolicymetadata:name:ksp-block-mysql-dirnamespace:wordpress-mysqlspec:message:Alert! Attempt to make changes to database detectedtags: - CIS - CIS_Linuxselector:matchLabels:app:mysqlfile:matchDirectories: - dir:/var/lib/mysql/ownerOnly:truereadOnly:trueseverity:1action:Block
apiVersion:security.kubearmor.com/v1kind:KubeArmorPolicymetadata:name:ksp-block-stig-v-81883-restrict-access-to-config-filesnamespace:wordpress-mysqlspec:tags: - config-filesmessage:Alert! configuration files have been accessedselector:matchLabels:app:wordpressfile:matchPatterns: - pattern:/**/*.confownerOnly:trueaction:Block
root@ubuntu-1-deployment-f987bd4d6-xzcb8:/#tcpdumptcpdump:eth0:Youdon't have permission to capture on that device(socket: Operation not permitted)root@ubuntu-1-deployment-f987bd4d6-xzcb8:/#
Policy Examples for Nodes/VMs
Here, we demonstrate how to define host security policies.
Explanation: The purpose of this policy is to block the execution of '/usr/bin/diff' in a host whose host name is 'kubearmor-dev'. For this, we define 'kubernetes.io/hostname: kubearmor-dev' in nodeSelector -> matchLabels and the specific path ('/usr/bin/diff') in process -> matchPaths. Also, we put 'Block' as the action of this policy.
Verification: After applying this policy, please open a new terminal (or connect to the host with a new session) and run '/usr/bin/diff'. You will see that /usr/bin/diff is blocked.
NOTE
The given policy works with almost every linux distribution. If it is not working in your case, check the process location. The following location shows location of sleep binary in different ubuntu distributions:
Explanation: The purpose of this policy is to audit any accesses to a critical file (i.e., '/etc/passwd'). Since we want to audit one critical file, we use matchPaths to specify the path of '/etc/passwd'.
Verification: After applying this policy, please open a new terminal (or connect to the host with a new session) and run 'sudo cat /etc/passwd'. Then, check the alert logs of KubeArmor.
Now, we will briefly explain how to define a host security policy.
Common
A security policy starts with the base information such as apiVersion, kind, and metadata. The apiVersion and kind would be the same in any security policies. In the case of metadata, you need to specify the name of a policy.
In the process section, there are three types of matches: matchPaths, matchDirectories, and matchPatterns. You can define specific executables using matchPaths or all executables in specific directories using matchDirectories. In the case of matchPatterns, advanced operators may be able to determine particular patterns for executables by using regular expressions. However, we generally do not recommend using this match.
If this is enabled, the owners of the executable(s) defined with matchPaths and matchDirectories will be only allowed to execute.
recursive
If this is enabled, the coverage will extend to the subdirectories of the directory defined with matchDirectories.
fromSource
If a path is specified in fromSource, the executable at the path will be allowed/blocked to execute the executables defined with matchPaths or matchDirectories. For better understanding, let us say that an operator defines a policy as follows. Then, /bin/bash will be only allowed (blocked) to execute /bin/sleep. Otherwise, the execution of /bin/sleep will be blocked (allowed).
In the case of capabilities, there is currently one match type: matchCapabilities. You can define specific capability names to allow or block using matchCapabilities. You can check available capabilities in Capability List.
In the case of syscalls, there are two types of matches, matchSyscalls and matchPaths. matchPaths can be used to target system calls targeting specific binary path or anything under a specific directory, additionally you can slice based on syscalls generated by a binary or a group of binaries in a directory. You can use matchSyscall as a more general rule to match syscalls from all sources or from specific binaries.
fromSource If a path is specified in fromSource, kubearmor will match only syscalls generated by the defined source. For better undrestanding, lets take the example below. Only unlink system calls generated by /bin/bash will be matched.
If this is enabled, the coverage will extend to the subdirectories of the directory.
Action
The action could be Audit or Block in general. In order to use the Allow action, you should define 'fromSource'; otherwise, all Allow actions will be ignored by default.
action: [Audit|Block]
If 'fromSource' is defined, we can use all actions for specific rules.
action: [Allow|Audit|Block]
For System calls monitoring, we only support audit mode no matter what the action is set to.
FAQs
What platforms are supported by KubeArmor? How can I check whether my deployment will be supported?
Use karmor probe to check if the platform is supported.
I am applying a blocking policy but it is not blocking the action. What can I check?
Checkout Binary Path
If the path in your process rule is not an absolute path but a symlink, policy enforcement won't work. This is because KubeArmor sees the actual executable path in events received from kernel space and is not aware about symlinks.
Policy enforcement on symbolic links like /usr/bin/python doesn't work and one has to specify the path of the actual executable that they link to.
Checkout Platform Support
Check karmor probe output and check whether Container Security is false. If it is false, the KubeArmor enforcement is not supported on that platform. You should check the KubeArmor Support Matrix and if the platform is not listed there then raise a new issue or connect to kubearmor community of slack.
Checkout Default Posture
If you are applying an Allow-based policies and expecting unknown actions to be blocked, please make sure to check the default security posture. The default security posture is set to Audit by default since KubeArmor v0.7.
How is KubeArmor different from PodSecurityPolicy/PodSecurityContext?
Native k8s supports specifying a security context for the pod or container. It requires one to specify native AppArmor, SELinux, seccomp policies. But there are a few problems with this approach:
All the OS distributions do not support the LSMs consistently. For e.g, GKE COS supports AppArmor while Bottlerocket supports SELinux and BPF-LSM.
The Pod Security Context expect the security profile to be specified in its native language, for instance, AppArmor profile for AppArmor. SELinux profile if SELinux is to be used. The profile language is extremely complex and this complexity could backfire i.e, it could lead to security holes.
Security Profile updates are manual and difficult: When an app is updated, the security posture might change and it becomes difficult to manually update the native rules.
No alerting of LSM violation on managed cloud platforms: By default LSMs send logs to kernel auditd, which is not available on most managed cloud platforms.
KubeArmor solves all the above mentioned problems.
It maps YAML rules to LSMs (apparmor, bpf-lsm) rules so prior knowledge of different security context (native AppArmor, SELinux) is not required.
It's easy to deploy: KubeArmor is deployed as a daemonset. Even when the application is updated, the enforcement rules are automatically applied.
Consistent Alerting: KubeArmor handles kernel events and maps k8s metadata using ebpf.
KubeArmor also runs in systemd mode so can directly run and protect Virtual Machines or Bare-metal machines too.
Pod Security Context cannot leverage BPF-LSM at all today. BPF-LSM provides more programmatic control over the policy rules.
Pod Security Context do not manage abstractions. As an example, you might have two nodes with Ubuntu, two nodes with Bottlerocket. Ubuntu, by default has AppArmor and Bottlerocket has BPF-LSM and SELinux. KubeArmor internally picks the right primitives to use for enforcement and the user do not have to bother explicitly stating what to use.
What is visibility that I hear of in KubeArmor and how to get visibility information?
KubeArmor, apart from been a policy enforcement engine also emits pod/container visibility data. It uses an eBPF-based system monitor which keeps track of process life cycles in containers and even nodes, and converts system metadata to container/node identities. This information can then be used for observability use-cases.
If you don't find an existing dashboard particular to your needs, feel free to create an issue. It would be really great if you could also contribute one!
How to fix `karmor logs` timing out?
karmor logs internally uses Kubernetes' client's port-forward. Port forward is not meant for long running connection and it times out if left idle. Checkout this StackOverflow answer for more info.
If you want to stream logs reliably there are a couple of solutions you can try:
Modiy the kubearmor service in kubearmor namespace and change the service type to NodePort. Then run karmor with:
This will create a direct, more reliable connection with the service, without any internal port-forward.
If you want to stream logs to external tools (fluentd/splunk/ELK etc) checkout Streaming KubeArmor events.
The community has created adapters and dashboards for some of these tools which can be used out of the box or as reference for creating new adapters. Checkout the previous question for more information.
How to get process events in the context of a specific pods?
Following command can be used to to get pod specific events:
karmor log --pod <pod_name>karmor log has following filter to provide more granularity:
--container - Specify container name for container specific logs
--logFilter <system|policy|all> - Filter to either receive system logs or alerts on policy violation
--logType <ContainerLog|HostLog> - Source of logs - ContainerLog: logs from containers or HostLog: logs from the host
--namespace - Specify the namespace for the running pods
--operation <Process|File|Network> - Type of logs based on process, file or network
How is KubeArmor different from admission controllers?
Kubernetes admission controllers are set of extensions that acts as a gatekeeper and help govern and control Kubernetes clusters. They intercept requests to the Kubernetes API server prior to the persistence of the object into etcd.
They can manage deployments requesting too many resources, enforce pod security policies, prevent vulnerable images from being deployed and check if the pod is running in privileged mode.
But all these checks are done before the pods are started. Admission controllers doesn't guarantee any protection once the vulnerability is inside the cluster.
KuberArmor protects the pods from within. It runs as a daemonset and restricts the behavior of containers at the system level. KubeArmor allows one to define security policies for the assets/resources (such as files, processes, volumes etc) within the pod/container, select those based on K8s metadata and simply apply these security policies at runtime.
It also detects any policy violations and generates audit logs with container identities. Apart from containers, KuberArmor also allows protecting the Host itself.
What are the Policy Actions supported by KubeArmor?
KubeArmor defines 3 policy actions: Allow, Block and Audit.
Allow: A whitelist policy or a policy defined with Allow action allows only the operations defined in the policy, rest everything is blocked/audited. Block: Policy defined with Block action blocks all the operations defined in the policy.
Audit: An applied Audit policy doesn't block any action but instead provides alerts on policy violation. This type of policy can be used for "dry-run" before safely applying a security policy in production.
If Block policy is used and there are no supported enforcement mechanism on the platform then the policy enforcement wouldn't be observed. But we will still be able to see the observability data for the applied Block policy, which can help us in identifying any suspicious activity.
How to use KubeArmor on Oracle K8s engine?
KubeArmor supports enforcement on OKE leveraging the BPF-LSM. The default kernel for Oracle Linux 8.6 (OL 8.6) is UEK R6 kernel-uek-5.4.17-2136.307.3 which does not support BPF-LSM.
Unbreakable Enterprise Kernel Release 7 (UEK R7) is based on Linux kernel 5.15 LTS that supports BPF-LSM and it's available for Oracle Linux 8 Update 5 onwards.
Installing UEK 7 on OL 8.6
UEK R7 can be installed on OL 8.6 by following the easy-to-follow instructions provided here in this Oracle Blog Post.
Note: After upgrading to the UEK R7 you may required to enable BPF-LSM if it's not enabled by default.
Note: These config could be in other places too like /boot/config, /usr/src/linux-headers-$(uname -r)/.config, /lib/modules/$(uname -r)/config, /proc/config.gz.
Checking if BPF-LSM is enabled
check if bpf is enabled by verifying if it is in the active lsms.
How to enable `KubeArmorHostPolicy` for k8s cluster?
By default the host policies and visibility is disabled for k8s hosts.
If you use following command, kubectl logs -n kubearmor <KUBEARMOR-POD> | grep "Started to protect"
you will see, 2023-08-21 12:58:34.641665 INFO Started to protect containers.
This indicates that only container/pod protection is enabled.
If you have hostpolicy enabled you should see something like this, 2023-08-22 18:07:43.335232 INFO Started to protect a host and containers
One can enable the host policy by patching the daemonset (kubectl edit daemonsets.apps -n kubearmor kubearmor):
This will enable the KubeArmorHostPolicy and host based visibility for the k8s worker nodes.
Using KubeArmor with Kind clusters
KubeArmor works out of the box with Kind clusters supporting BPF-LSM. However, with AppArmor only mode, Kind cluster needs additional provisional steps. You can check if BPF-LSM is supported/enabled on your host (on which the kind cluster is to be deployed) by using following:
cat /sys/kernel/security/lsm
If it has bpf in the list, then everything should work out of the box
If it has apparmor in the list, then follow the steps mentioned in this FAQ.
The above command will install the AppArmor utilities in the kind-control-plane, we can also use this command to install these in minikube as well as in all the other docker based Kubernetes environments.
It might be possible that apart from the dockerized kubenetes environment AppArmor might not be available on the master node itself in the Kubernetes cluster. To check for the same you can run the below command to check for the AppArmor support in kernel config:
cat /boot/config-$(uname -r) | grep -e "APPARMOR"
Following flags need to exist and set to y
CONFIG_SECURITY_APPARMOR=y
Run the command to install apparmor:
apt update && apt install apparmor-utils -y
You need to restart your CRI in-order to make APPARMOR available as a kernel config security.
If not then we need to install AppArmor utils on the master node itself.
If the kubearmor-relay pod goes into CrashLoopBackOff, apply the following patch:
kubectl patch deploy -n $(kubectl get deploy -l kubearmor-app=kubearmor-relay -A -o custom-columns=:'{.metadata.namespace}',:'{.metadata.name}') --type=json -p='[{"op": "add", "path": "/spec/template/metadata/annotations/container.apparmor.security.beta.kubernetes.io~1kubearmor-relay-server", "value": "unconfined"}]'
Debug KubeArmor installation issue
In certain scenarios, the expected behavior of KubeArmor might not be observed. One way to investigate this is by using the KubeArmor Command Line Interface (CLI) utility, commonly referred to as [karmor cli](https://github.com/kubearmor/kubearmor-client).
To check the status and configuration of KubeArmor, you can use the following command:
When executing this command, check the output for the value of ActiveLSM field, if it is not assigned any value, it means that no active LSM is available for KubeArmor to enforce policies. Under normal circumstances, this value should be assigned a specific Linux Security Module (LSM) that KubeArmor uses to enforce security policies. Additionally, ensure that the Container Security field is set to true.
However, there are situations where ActiveLSM might not be assigned any value. This situation indicates that Kubearmor is unable to identify the appropriate LSM in a environment, which is commonly used in Kubernetes setups.
To address this issue, KubeArmor provides a solution involving the use of BPF-LSM. BPF (Berkeley Packet Filter) is a technology that allows efficient packet filtering in the Linux kernel. Enabling support for BPF LSM ensures that KubeArmor can apply and enforce policies as expected in Dockerized environments associated with Kubernetes. Please note that BPFLSM is only available on kernel versions above 5.8 or on RHEL distros > 8.5.
So we need to enable bpf-lsm for Kubearmor to apply and enforce policies as expected.
You can also enable AppArmor if you want to use it as a security module to enforce KubeArmor policies, please refer here. There is a chance that neither AppArmor nor BPF-LSM is enabled on some nodes.
We can apply the following manifest which automatically detects and installs BPFLSM/AppArmor whichever is needed in kubernetes worker nodes.
Warning: After running the above script the nodes will restart.
Contribution Guide
KubeArmor maintainers welcome individuals and organizations from across the cloud security landscape (creators and implementers alike) to make contributions to the project. We equally value the addition of technical contributions and enhancements of documentation that helps us grow the community and strengthen the value of KubeArmor. We invite members of the community to contribute to the project!
To make a contribution, please follow the steps below.
Fork this repository (KubeArmor)
First, fork this repository by clicking on the Fork button (top right).
Then, click your ID on the pop-up screen.
This will create a copy of KubeArmor in your account.
Clone the repository
Now clone Kubearmor locally into your dev environment.
This will clone a copy of Kubearmor installed in your dev environment.
Make changes
First, go into the repository directory and make some changes.
Please refer to development guide to set up your environment for KubeArmor contribution.
Check the changes
Please run "test_kubearmor.sh" before committing the changes
cd KubeArmor/KubeArmor/build
~/KubeArmor/KubeArmor/build$ ./test_kubearmor.sh
If you see any warnings or errors, please fix them first.
Commit changes
Please see your changes using "git status" and add them to the branch using "git add".
$ cd KubeArmor
~/KubeArmor$ git status
~/KubeArmor$ git add [changed file]
Then, commit the changes using the "git commit" command.
~/KubeArmor$ git commit -s -m "Add a new feature by [your name]"
Please make sure that your changes are properly tested on your machine.
Push changes to your forked repository
Push your changes using the "git push" command.
~/KubeArmor$ git push
Create a pull request with your changes with the following steps
First, go to your repository on GitHub.
Then, click "Pull request" button.
After checking your changes, click 'Create pull request'.
A pull request should contain the details of all commits as specific as possible, including "Fixes: #(issue number)".
Finally, click the "Create pull request" button.
The changes would be merged post a review by the respective module owners. Once the changes are merged, you will get a notification, and the corresponding issue will be closed.
DCO Signoffs
To ensure that contributors are only submitting work that they have rights to, we are requiring everyone to acknowledge this by signing their work. Any copyright notices in this repo should specify the authors as "KubeArmor authors".
To sign your work, just add a line like this at the end of your commit message:
This can easily be done with the -s or --signoff option to git commit.
By doing this, you state that the source code being submitted originated from you (see https://developercertificate.org).
Testing Guide
Testing Guide
There are two ways to check the functionalities of KubeArmor: 1) testing KubeArmor manually and 2) using the testing framework.
0. Make sure that the annotation controller is installed on the cluster (Applicable for Steps 1 and 2)
To install the controller from KubeArmor docker repository to your cluster run
To install the controller (local version) to your cluster run
1. Test KubeArmor manually
1.1. Run 'kubectl proxy' in background
1.2. Compile KubeArmor
1.3. Run KubeArmor
1.4. Apply security policies into Kubernetes
Beforehand, check if the KubeArmorPolicy and KubeArmorHostPolicy CRDs are already applied.
If they are still not applied, do so.
Now you can apply specific policies.
1.5. Trigger policy violations to generate alerts
1.6. Check generated alerts
flags:
Note that you will see alerts and logs generated right after karmor runs logs; thus, we recommend to run the above command in other terminal to see logs live.
2. Test KubeArmor using the auto-testing framework
2.1. Prepare microservices and test scenarios
The auto-testing framework operates based on two things: microservices and test scenarios for each microservice.
Microservices
Then, create YAML files for the microservice
Test scenarios
Then, define a YAML file for a test policy in the directory
Create cmd files whose names are like 'cmd#'
Here is a template for a cmd file.
This is a cmd example of a test scenario.
2.2. Test KubeArmor
The case that KubeArmor is directly running in a host
Compile KubeArmor
Run the auto-testing framework
Check the test report
The case that KubeArmor is running as a daemonset in Kubernetes
Run the testing framework
Check the test report
Development Guide
Development
1. Vagrant Environment (Recommended)
Requirements
Here is the list of requirements for a Vagrant environment
Clone the KubeArmor github repository in your system
Install Vagrant and VirtualBox in your environment, go to the vagrant path and run the setup.sh file
VM Setup using Vagrant
Now, it is time to prepare a VM for development.
To create a vagrant VM
Output will show up as ...
To get into the vagrant VM
Output will show up as ...
To destroy the vagrant VM
VM Setup using Vagrant with Ubuntu 21.10 (v5.13)
To use the recent Linux kernel v5.13 for dev env, you can run make with the NETNEXT flag set to 1 for the respective make option.
You can also make the setting static by changing NETNEXT=0 to NETNEXT=1 in the Makefile.
2. Self-managed Kubernetes
Requirements
Here is the list of minimum requirements for self-managed Kubernetes.
Alternative Setup
You can try the following alternative if you face any difficulty in the above Kubernetes (kubeadm) setup.
Note Please make sure to set up the alternative k8s environment on the same host where the KubeArmor development environment is running.
K3s
MicroK8s
No Support - Docker Desktops
KubeArmor does not work with Docker Desktops on Windows and macOS because KubeArmor integrates with Linux-kernel native primitives (including LSMs).
Development Setup
In order to install all dependencies, please run the following command.
Now, you are ready to develop any code for KubeArmor. Enjoy your journey with KubeArmor.
3. Environment Check
Compilation
Check if KubeArmor can be compiled on your environment without any problems.
If you see any error messages, please let us know the issue with the full error messages through KubeArmor's slack.
Execution
In order to directly run KubeArmor in a host (not as a container), you need to run a local proxy in advance.
Then, run KubeArmor on your environment.
Note If you have followed all the above steps and still getting the warning The node information is not available, then this could be due to the case-sensitivity discrepancy in the actual hostname (obtained by running hostname) and the hostname used by Kubernetes (under kubectl get nodes -o wide).
K8s converts the hostname to lowercase, which results in a mismatch with the actual hostname.
To resolve this, change the hostname to lowercase using the command hostnamectl set-hostname <lowercase-hostname>.
KubeArmor Controller
Starting from KubeArmor v0.11 - annotations, container policies, and host policies are handled via kubearmor controller, the controller code can be found under pkg/KubeArmorController.
To install the controller from KubeArmor docker repository run
To install the controller (local version) to your cluster run
if you need to setup a local registry to push you image, use docker-registry.sh script under ~/KubeArmor/contribution/local-registry directory
Code Directories
Here, we briefly give you an overview of KubeArmor's directories.
Source code for KubeArmor (/KubeArmor)
Source code for KubeArmor Controller (CRD)
Deployment tools and files for KubeArmor
Files for testing
You can refer to security policies defined for example microservices in .
Watch alerts using cli tool
Create a directory for a microservice in
As an example, we created 'multiubuntu' in and defined 'multiubuntu-deployment.yaml' in .
Create a directory whose name is like '[microservice name]_[scenario name]' in
You can refer to predefined testcases in .
Note Skip the steps for the vagrant setup if you're directly compiling KubeArmor on the Linux host. Proceed to setup K8s on the same host by resolving any dependencies.
KubeArmor is designed for Kubernetes environment. If Kubernetes is not setup yet, please refer to . KubeArmor leverages CRI (Container Runtime Interfaces) APIs and works with Docker or Containerd or CRIO based container runtimes. KubeArmor uses LSMs for policy enforcement; thus, please make sure that your environment supports LSMs (either AppArmor or bpf-lsm). Otherwise, KubeArmor will operate in Audit-Mode with no policy "enforcement" support.
You can also develop and test KubeArmor on K3s instead of the self-managed Kubernetes. Please follow the instructions in .
You can also develop and test KubeArmor on MicroK8s instead of the self-managed Kubernetes. Please follow the instructions in .
will automatically install , , , and some other dependencies.
$ cd KubeArmor/pkg/KubeArmorAnnotation
~/KubeArmor/pkg/KubeArmorAnnotation$ make deploy
$ cd KubeArmor/pkg/KubeArmorAnnotation
~/KubeArmor/pkg/KubeArmorAnnotation$ make docker-build deploy
$ kubectl proxy &
$ cd KubeArmor/KubeArmor
~/KubeArmor/KubeArmor$ make clean && make
--gRPC string gRPC server information
--help help for log
--json Flag to print alerts and logs in the JSON format
--logFilter string What kinds of alerts and logs to receive, {policy|system|all} (default "policy")
--logPath string Output location for alerts and logs, {path|stdout|none} (default "stdout")
--msgPath string Output location for messages, {path|stdout|none} (default "none")
$ cd KubeArmor/KubeArmor
~/KubeArmor/KubeArmor$ make
$ kubectl proxy &
$ cd KubeArmor/KubeArmor
~/KubeArmor/KubeArmor$ make run
$ cd KubeArmor/pkg/KubeArmorController
~/KubeArmor/pkg/KubeArmorController$ make deploy
$ cd KubeArmor/pkg/KubeArmorController
~/KubeArmor/pkg/KubeArmorController$ make docker-build deploy
KubeArmor/
BPF - eBPF code for system monitor
common - Libraries internally used
config - Configuration loader
core - The main body (start point) of KubeArmor
enforcer - Runtime policy enforcer (enforcing security policies into LSMs)
feeder - gRPC-based feeder (sending audit/system logs to a log server)
kvmAgent - KubeArmor VM agent
log - Message logger (stdout)
monitor - eBPF-based system monitor (mapping process IDs to container IDs)
policy - gRPC service to manage Host Policies for VM environments
types - Type definitions
protobuf/ - Protocol buffer
pkg/KubeArmorController/ - KubeArmorController generated by Kube-Builder for KubeArmor Annotations, KubeArmorPolicy and KubeArmorHostPolicy
deployments/
<cloud-platform-name> - Deployments specific to respective cloud platform (deprecated - use karmor install or helm)
controller - Deployments for installing KubeArmorController alongwith cert-manager
CRD - KubeArmorPollicy and KubeArmorHostPolicy CRDs
get - Stores source code for deploygen, a tool used for specifying kubearmor deployments
helm/
KubeArmor - KubeArmor's Helm chart
KubeArmorOperator - KubeArmorOperator's Helm chart
examples/ - Example microservices for testing
tests/ - Automated test framework for KubeArmor