CVE-2026-74512 audit: fix potential use-after-free in audit_del_rule()
A use-after-free in the Linux kernel audit subsystem allows attackers to potentially execute code or escalate privileges during rule deletion.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74512?
CVE-2026-74512 is a high-severity use after free vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
audit: fix potential use-after-free in audit_del_rule()
`audit_del_rule()` destroys `e->rule.exe` via `audit_remove_mark_rule()` before unlinking the rule from RCU-visible filter lists and waiting for a grace period. Concurrent readers in `audit_filter()` and `audit_filter_rules()` still dereference `e->rule.exe`, while the fsnotify mark can be freed on an independent lifetime path. This creates a use-after-free window during rule deletion.
Fix this by unlinking the rule from the RCU-visible lists and invoking `synchronize_rcu()` before calling `audit_remove_mark_rule()` (and other rule removal helpers). This ensures that all existing RCU readers have exited the critical section before any underlying resources are destroyed.
Which versions are affected by CVE-2026-74512?
How do I fix CVE-2026-74512?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-74512 being exploited?
There is no known exploitation of CVE-2026-74512 in the wild and no public exploit code.
Sources
Also known as AZL-96540, BELL-CVE-2026-74512, DEBIAN-CVE-2026-74512, GHSA-4248-7w5j-8g9p, UBUNTU-CVE-2026-74512.