CVE-2026-52977EPSS p2.4%
CVE-2026-52977CVE-2026-52977
linux / linux_kernel
Description
In the Linux kernel, the following vulnerability has been resolved:
futex: Prevent lockup in requeue-PI during signal/ timeout wakeup
During wait-requeue-pi (task A) and requeue-PI (task B) the following
race can happen:
Task A Task B
futex_wait_requeue_pi()
futex_setup_timer()
futex_do_wait()
futex_requeue()
CLASS(hb, hb1)(&key1);
CLASS(hb, hb2)(&key2);
*timeout*
futex_requeue_pi_wakeup_sync()
requeue_state = Q_REQUEUE_PI_IGNORE
*blocks on hb->lock*
futex_proxy_trylock_atomic()
futex_requeue_pi_prepare()
Q_REQUEUE_PI_IGNORE => -EAGAIN
double_unlock_hb(hb1, hb2)
*retry*
Task B acquires both hb lock
Scoring
| CVSS | 5.5 () |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| EPSS | 0.12% probability of exploitation · percentile 2.4% · 2026-08-11T12:00:17Z |
| Last modified | 2026-07-14 |