C-0194 - Minimize the admission of containers wishing to share the host process ID namespace
Framework
cis-v1.23-t1.0.1
Severity
Medium
Description of the the issue
A container running in the host's PID namespace can inspect processes running outside the container. If the container also has access to ptrace capabilities this can be used to escalate privileges outside of the container.
There should be at least one admission control policy defined which does not permit containers to share the host PID namespace.
If you need to run containers which require hostPID, this should be defined in a separate policy and you should carefully check to ensure that only limited service accounts and users are given permission to use that policy.
Related resources
MutatingWebhookConfiguration, Namespace, ValidatingWebhookConfiguration
What does this control test
Do not generally permit containers to be run with the hostPID
flag set to true.
How to check it manually
List the policies in use for each namespace in the cluster, ensure that each policy disallows the admission of hostPID
containers
Remediation
Add policies to each namespace in the cluster which has user workloads to restrict the admission of hostPID
containers.
Impact Statement
Pods defined with spec.hostPID: true
will not be permitted unless they are run under a specific policy.
Default Value
By default, there are no restrictions on the creation of hostPID
containers.
Example
No example
Updated 9 days ago