This vulnerability involves improper privilege management in CRIU's handling of restartable sequences (rseq) during checkpoint/restore operations. A malicious container process can register an rseq critical section that hijacks CRIU's parasite code injection during checkpointing, allowing it to spoof the process credentials saved in the checkpoint image. Upon restore, the process gains elevated capabilities and zeroed user and group IDs. Exploitation requires checkpoint/restore functionality enabled with root privileges (podman) or cluster-admin RBAC (OpenShift) and cannot be triggered from inside the container. Red Hat products mitigate the impact through user namespaces, SELinux type enforcement, seccomp filters, and kernel mount namespace ownership checks, which prevent privilege escalation and container escape despite spoofed credentials. The vulnerability is scored 7.8 CVSS v3.1 (high severity) with local attack vector, high complexity, low privileges required, no user interaction, and scope changed. The vulnerability is documented in Red Hat's advisory and related CRIU upstream fixes exist.

Successful exploitation allows a malicious process inside a container to spoof its credentials during checkpoint, resulting in elevated capabilities and zeroed UIDs/GIDs on restore. This grants full discretionary access control bypass within the container namespace, potentially allowing privilege escalation within the container. However, the impact is limited by the requirement for checkpoint/restore to be enabled with elevated privileges, and multiple Red Hat security mechanisms (SELinux, seccomp, user namespaces, kernel mount namespace checks) prevent privilege escalation from extending beyond the container or host compromise. No known exploits in the wild have been reported.

Disable checkpoint/restore functionality in the container runtime if it is not required, as it is not enabled by default in most Red Hat products. If checkpoint/restore is needed, ensure containers run with user namespaces enabled to limit the scope of spoofed capabilities to the user namespace. Red Hat's SELinux enforcement, seccomp filters, and kernel mount namespace ownership checks provide additional defense-in-depth. Monitor Red Hat advisories for official patches or updates. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.