CVE-2025-21786 – Linux Kernel Workqueue Use-After-Free Vulnerability

The following table lists the changes that have been made to the
CVE-2025-21786 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution
of a vulnerability, and for identifying the most recent changes that may
impact the vulnerability’s severity, exploitability, or other characteristics.

  • New CVE Received
    by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Feb. 27, 2025

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved:

    workqueue: Put the pwq after detaching the rescuer from the pool

    The commit 68f83057b913(“workqueue: Reap workers via kthread_stop() and
    remove detach_completion”) adds code to reap the normal workers but
    mistakenly does not handle the rescuer and also removes the code waiting
    for the rescuer in put_unbound_pool(), which caused a use-after-free bug
    reported by Cheung Wall.

    To avoid the use-after-free bug, the pool’s reference must be held until
    the detachment is complete. Therefore, move the code that puts the pwq
    after detaching the rescuer from the pool.

    Added Reference https://git.kernel.org/stable/c/835b69c868f53f959d4986bbecd561ba6f38e492
    Added Reference https://git.kernel.org/stable/c/e76946110137703c16423baf6ee177b751a34b7e
    Added Reference https://git.kernel.org/stable/c/e7c16028a424dd35be1064a68fa318be4359310f
Share the Post:

Related Posts