Use-after-free in Linux kernel - CVE-2026-74503
Published: August 16, 2026
Vulnerability identifier: #VU143274
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-74503
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
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 ALSA timer subsystem when reopening and closing timer instances after a failed fallback open. A local user can forge a sequencer queue key and trigger a failed reopen sequence to cause a denial of service.
Exploitation requires access to /dev/snd/timer and /dev/snd/seq.
Affected software
Linux kernel
Debian Linux
linux (Debian package)
Debian Linux
linux (Debian package)
How to mitigate CVE-2026-74503
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
linux (Debian package) - update to 6.12.105-1
linux (Debian package) - update to 6.12.105-1