CVE-2026-89643

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

audit: avoid dropping live tree ref on fsnotify rule autoremove

audit_del_rule() is used for both netlink deletion templates and internal

fsnotify autoremove. The former passes a parsed template which owns a

temporary tree reference; the latter passes the installed entry itself.

The unconditional audit_put_tree() at the end of audit_del_rule() assumes

the template case. For mixed AUDIT_DIR plus AUDIT_EXE rules, an fsnotify

autoremove event therefore drops the installed rule's live tree reference.

Repeating this across rules sharing the same tree can free the tree while

another rule still references it, and a later autoremove dereferences the

freed pathname while comparing rules.

Move the temporary-tree put to audit_rule_change(), the caller that owns

deletion templates. Keep it in the AUDIT_DEL_RULE cleanup so both

successful deletion and -ENOENT still release the parser-owned tree.

[PM: dropped unnecessary com

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References