Use-after-free in Linux kernel - CVE-2026-74479

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in the pktgen proc entry handling in net/core/pktgen.c when concurrently removing and renaming pktgen devices. A local user can trigger a race condition involving proc_remove() on a stale proc_dir_entry to cause a denial of service.

The issue occurs because pktgen_change_name() and pktgen_remove_device() access the same proc entry with inconsistent locking, and exploitation requires winning a race between those paths.

Affected software

How to mitigate CVE-2026-74479

External References

• https://git.kernel.org/stable/c/4ef801b838d85c0ea5852c50667f7344ce3b6cd0
• https://git.kernel.org/stable/c/817ff6efdb7f484ea547218e11e17d8e43daa3b4
• https://git.kernel.org/stable/c/b006a5404470bd3eb2aa0425fc447183032047ef

Related Security Bulletins

• Use-after-free in Linux kernel core
• Debian update for linux