CVE-2026-80777
Received
Received - Intake
Race Condition in Linux Kernel Futex PI Mechanism
Vulnerability report for CVE-2026-80777, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-04
Last updated on: 2026-09-04
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
futex/pi: Plug private futex exec() race
The check for private futexes whether the waiter's mm, which is stored in
the futex_key and copied into the pi_state, is the same as the owner's mm
is not sufficient for exec(). exec() has a gap where the mm check fails to
give the correct answer:
exec()
...
exec_release_mm()
futex_exec_release()
tsk::futex::exit_state = EXITING;
cleanup_robust_list();
1) tsk::futex::exit_state = OK;
...
old_mm = tsk::mm;
2) tsk::mm = ->mm;
Between #1 and #2 the check for the mm is wrong as that mm is about to be
swapped out and eventually freed.
Plug this gap by:
1) Setting tsk::futex::exit_state to FUTEX_STATE_DEAD in
futex_exec_release()
2) Setting tsk::futex::exit_state to FUTEX_STATE_OK after
the mm has been switched.
From a futex point of view the task is dead after it finished the robust
list cleanup up to the point where it sets the state to OK again.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
