CVE-2026-72389
Description
In the Linux kernel, the following vulnerability has been resolved: bridge: stp: Fix a potential use-after-free when deleting a bridge The three STP timers are not supposed to be armed while the bridge is administratively down. They are synchronously deactivated when the bridge is put administratively down and the various call sites check for 'IFF_UP' before arming them. This check is missing from br_topology_change_detection() and it is possible to engineer a situation in which the topology change timer is armed while the bridge is administratively down, resulting in a use-after-free [1] when the bridge is deleted. Fix by adding the missing check and for good measures synchronously shutdown the three timers when the bridge is deleted. [1] ODEBUG: free active (active state 0) object: ffff88811662b9b0 object type: timer_list hint: br_topology_change_timer_expired (net/bridge/br_stp_timer.c:120) WARNING: lib/debugobjects.c:629 at debug_print_object+0x1bc/0x450, CPU#9: ip/359
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://git.kernel.org/stable/c/297a747f59bff6573196d7236178144d66524e68
- https://git.kernel.org/stable/c/2a00517db8de4be7df3d483b215c5544fb30a191
- https://git.kernel.org/stable/c/39283907a25e5caf0f2bd2947f6e56644b01e2b7
- https://git.kernel.org/stable/c/40cbfa3a28e0919469d1b086629bb3ce38a83593
- https://git.kernel.org/stable/c/4c40eec06eeac37c58e47a6058eb32901218d5d4
- https://git.kernel.org/stable/c/b4b3458ef88df4798632619f018791d4344bcd92
- https://git.kernel.org/stable/c/c86579b0a2d201792bcb59316629f4ba4758cfc8
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.