GHSA-cm9x-c3rh-7rc4 CRI-O vulnerable to /etc/passwd tampering resulting in Privilege Escalation

• Go github.com/cri-o/cri-o: < 1.26.0 → fixed in 1.26.0

Impact It is possible to craft an environment variable with newlines to add entries to a container's /etc/passwd. It is possible to circumvent admission validation of username/UID by adding such an entry. Note: because the pod author is in control of the container's /etc/passwd, this is not considered a new risk factor. However, this advisory is being opened for transparency and as a way of tracking fixes. Patches 1.26.0 will have the fix. More patches will be posted as they're available. Workarounds Additional security controls like SELinux should prevent any damage a container is able to do with root on the host. Using SELinux is recommended because this class of attack is already possible by manually editing the container's /etc/passwd References