CVE-2026-53273
Description
In the Linux kernel, the following vulnerability has been resolved: tee: optee: prevent use-after-free when the client exits before the supplicant Commit 70b0d6b0a199 ("tee: optee: Fix supplicant wait loop") made the client wait as killable so it can be interrupted during shutdown or after a supplicant crash. This changes the original lifetime expectations: the client task can now terminate while the supplicant is still processing its request. If the client exits first it removes the request from its queue and kfree()s it, while the request ID remains in supp->idr. A subsequent lookup on the supplicant path then dereferences freed memory, leading to a use-after-free. Serialise access to the request with supp->mutex: * Hold supp->mutex in optee_supp_recv() and optee_supp_send() while looking up and touching the request. * Let optee_supp_thrd_req() notice that the client has terminated and signal optee_supp_send() accordingly. With these changes the request cannot be freed while the supplicant still has a reference, eliminating the race.
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.
OS impact
Debian Mixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 6.12.94-1 |
| sid | Fixed | 7.0.13-1 |
| forky | Affected | — |
| bullseye | Affected | — |
| bookworm | Affected | — |
References
- https://git.kernel.org/stable/c/416259cb5bffecaaae5f76539deb535a8c1b2c34
- https://git.kernel.org/stable/c/724d0caffd4204b46f78efe22f18f8338031c6e1
- https://git.kernel.org/stable/c/ae847ab29ded2d7cece4d5970f0edefa4137bf2f
- https://git.kernel.org/stable/c/9a0dc9279d0907b198f205a693aedf696b08145d
- https://git.kernel.org/stable/c/d366a01475f927402c96a3fe78bfc06b924fc87d
- https://git.kernel.org/stable/c/d5b57bb314d79e99bebb58a53588fa11dd4dbf69
- https://git.kernel.org/stable/c/373152c94e57e9592b68c100e224fbd943cfd608
- https://git.kernel.org/stable/c/387a926ee166814611acecb960207fe2f3c4fd3e
- https://security-tracker.debian.org/tracker/CVE-2026-53273
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.