SB20260812164 - Use-after-free in Linux kernel watchdog driver
Published: August 12, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-68357)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 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]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in watchdog_unregister_governor() and the watchdog pretimeout governor handling logic when unregistering a watchdog governor that is still referenced as default_gov. A local user can trigger governor unregistration and subsequent watchdog device registration or reassignment to cause a denial of service.
The issue occurs when the unregistered governor remains referenced through a dangling default_gov pointer, affecting both newly registered watchdog devices and existing devices whose governor is reassigned.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/0ca252720f0e38411cfec3431db9bb1aed0a412c
- https://git.kernel.org/stable/c/2e47b91b9b4020fcc01def14d6b6556d66074cf4
- https://git.kernel.org/stable/c/7362ba0f9c96ac3ad6a2ca3995bd9fc9a28a8661
- https://git.kernel.org/stable/c/7993d626983cc58fbde9607333cfd2d57725c197
- https://git.kernel.org/stable/c/7d1658b066de30f4b23afc14814d22416a971e6e