CVEvulnerability
CVE-2026-80928
7.8 HIGH
Official page ↗
- Status
- Received
- Published
- 2026-09-11
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
smack: fix cred UAF in smack_file_send_sigiotask()
When inspecting the credentials of another task, objective credentials
(->real_cred, accessed with __task_cred()) must always be used.
Accessing ->cred on a non-current task is forbidden unless that task is
being created or destroyed; a task is allowed to change its own ->cred
pointer with no synchronization, and changing ->cred should only affect the
current syscall.
smack_file_send_sigiotask() was accessing both sets of credentials: First
tsk->cred, then __task_cred(tsk).
Fix it, always access the objective credentials here.
I have tested that this bug can lead to a KASAN-reported UAF of struct cred
in smack_file_send_sigiotask(), and that this fix prevents the race.
References
- https://git.kernel.org/stable/c/7c7fe043f3099d0d35002b248967f75e55345b93 git.kernel.org
- https://git.kernel.org/stable/c/a512366d84e134a9eefc2cc40eeb6e80e2ec162c git.kernel.org
- https://git.kernel.org/stable/c/b5bcf3adfa27279da4401ab8f1e1a706601a92be git.kernel.org
- https://git.kernel.org/stable/c/b791401bf389a1546a830d2b381ca60fe94c7870 git.kernel.org
- https://git.kernel.org/stable/c/ed64aa505875a3b4defd504ee8e59e1949246a62 git.kernel.org
- https://git.kernel.org/stable/c/f9c7b1f2b9d8f4176d2632743f51400855978ace git.kernel.org
- https://git.kernel.org/stable/c/fedc88e38ce979a720cd2de042578cb5df3dc8de git.kernel.org