A flaw was found in cri-o, where containers were incorrectly started with non-empty default permissions. A vulnerability was found in Moby (Docker Engine) where containers started incorrectly with non-empty inheritable Linux process capabilities. This flaw allows an attacker with access to programs with inheritable file capabilities to elevate those capabilities to the permitted set when execve(2) runs.

Affected: Go: github.com/cri-o/cri-o

### Impact

A bug was found in CRI-O where containers were incorrectly started with non-empty inheritable Linux process capabilities, creating an atypical Linux environment and enabling programs with inheritable file capabilities to elevate those capabilities to the permitted set during `execve(2)`. Normally, when executable programs have specified permitted file capabilities, otherwise unprivileged users and processes can execute those programs and gain the specified file capabilities up to the bounding set. Due to this bug, containers which included executable programs with inheritable file capabilities allowed otherwise unprivileged users and processes to additionally gain these inheritable file capabilities up to the container's bounding set. Containers which use Linux users and groups to perform privilege separation inside the container are most directly impacted.

This bug did not affect the container security sandbox as the inheritable set never contained more capabilities than were included in the container's bounding set.

### Patches

This bug will been fixed in the following versions of CRI-O: - v1.24.0

Users should update to the version corresponding to their minor release as soon as possible. Running containers should be stopped, deleted, and recreated for the inheritable capabilities to be reset.

This fix changes CRI-O behavior such that containers are started with a more typical Linux environment. Refer to `capabilities(7)` for a description of how cap…

cri-o: Default inheritable capabilities for linux container should be empty