C-0219 - Minimize the admission of containers with added capabilities
Framework
cis-eks-t1.2.0, cis-aks-t1.2.0
Severity
Medium
Description of the the issue
Containers run with a default set of capabilities as assigned by the Container Runtime. Capabilities outside this set can be added to containers which could expose them to risks of container breakout attacks.
There should be at least one PodSecurityPolicy (PSP) defined which prevents containers with capabilities beyond the default set from launching.
If you need to run containers with additional capabilities, this should be defined in a separate PSP and you should carefully check RBAC controls to ensure that only limited service accounts and users are given permission to access that PSP.
Related resources
PodSecurityPolicy
What does this control test
Do not generally permit containers with capabilities assigned beyond the default set.
How to check it manually
Get the set of PSPs with the following command:
kubectl get psp
Verify that there are no PSPs present which have allowedCapabilities
set to anything other than an empty array.
Remediation
Ensure that allowedCapabilities
is not present in PSPs for the cluster unless it is set to an empty array.
Impact Statement
Pods with containers which require capabilities outwith the default set will not be permitted.
Default Value
By default, PodSecurityPolicies are not defined. If a PSP is created 'allowedCapabilities' is set by default.
Example
No example
Updated 3 months ago