CVE-2026-74512
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk3th percentile - higher than 3% of all known CVEs
Summary
In the Linux kernel, in the audit module, a potential use-after-free vulnerability was found in audit_del_rule(). This function 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. The fix unlinks the rule from RCU-visible lists and invokes synchronize_rcu() before calling audit_remove_mark_rule() and other rule removal helpers.
Risk Assessment
The vulnerability may lead to use-after-free, which could result in system crash, privilege escalation, or information disclosure.
Recommendation
Apply a Linux kernel update containing the fix for CVE-2026-74512. Restrict access to audit functionality for untrusted users.
Original NVD description (English source)
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.