An AppArmor SAUCE patch within the Ubuntu kernel incorrectly causes the system to sleep while a spinlock is held during notification handling, which can lead to a deadlock or kernel panic. The flaw permits an unprivileged local user to trigger the bug via normal interactions with AppArmor, resulting in the kernel halting. The weakness matches CWE‑833, illustrating improper synchronization leading to resource starvation.

The vulnerability affects Canonical’s Ubuntu Linux kernels 6.8, 6.17, and 7.0. Systems running these kernel releases are susceptible because the AppArmor SAUCE patch is present and exhibits the faulty sleep behavior.

With a CVSS base score of 5.5 the risk is moderate, and the issue is not listed in the CISA KEV catalog nor does it have an EPSS score provided. The attack requires only local execution by an unprivileged user, so the likelihood in a typical environment is low to moderate, but if compromised users can trigger the bug the result would be a denial of service via kernel panic or deadlock.