CVE-2026-89643

Critical

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 comment for line length reasons]

SeverityCritical
CVSS9.8
Exploit probability—
ProductLinux
PublishedSep 11, 2026
First seenSep 11, 2026

How to fix

Update
  • Linux Linux9cac21f8eb82675ed19fb955b8bbb9dd14cc3d58, b322cc7adcd2e6ec1594d187533a126506ab545c, 695c85dc345a4e0292739f004c261bedef3f27e6, 01b0ec8c397be65ff710777c97017ca1de56ef8e, cf37b61b5420fd4600fe78cf8c24da6e4d9bfe28, 636a99bab36ba27515363d325866c0273ac83b3e, 583cf579b32d99e3fe4e9c8ecc4d852e3708fbec, 783f0f0974c156aca630f4ffff248671082a098d or later

Affected products

ProductAffected versionsFixed in
Linux Linux34d99af52ad40bd498ba66970579a5bc1fb1a3bc ≤ v < 9cac21f8eb82675ed19fb955b8bbb9dd14cc3d58, 34d99af52ad40bd498ba66970579a5bc1fb1a3bc ≤ v < b322cc7adcd2e6ec1594d187533a126506ab545c, 34d99af52ad40bd498ba66970579a5bc1fb1a3bc ≤ v < 695c85dc345a4e0292739f004c261bedef3f27e6, 34d99af52ad40bd498ba66970579a5bc1fb1a3bc ≤ v < 01b0ec8c397be65ff710777c97017ca1de56ef8e, 34d99af52ad40bd498ba66970579a5bc1fb1a3bc ≤ v < cf37b61b5420fd4600fe78cf8c24da6e4d9bfe28, 34d99af52ad40bd498ba66970579a5bc1fb1a3bc ≤ v < 636a99bab36ba27515363d325866c0273ac83b3e, 34d99af52ad40bd498ba66970579a5bc1fb1a3bc ≤ v < 583cf579b32d99e3fe4e9c8ecc4d852e3708fbec, 34d99af52ad40bd498ba66970579a5bc1fb1a3bc ≤ v < 783f0f0974c156aca630f4ffff248671082a098d, 4.39cac21f8eb82675ed19fb955b8bbb9dd14cc3d58, b322cc7adcd2e6ec1594d187533a126506ab545c, 695c85dc345a4e0292739f004c261bedef3f27e6, 01b0ec8c397be65ff710777c97017ca1de56ef8e, cf37b61b5420fd4600fe78cf8c24da6e4d9bfe28, 636a99bab36ba27515363d325866c0273ac83b3e, 583cf579b32d99e3fe4e9c8ecc4d852e3708fbec, 783f0f0974c156aca630f4ffff248671082a098d

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CVE-2026-89643 · Linux · Dark Radar