CVE-2026-68357
Received Received - Intake

Use-After-Free in Linux Kernel Watchdog Subsystem

Publication date: 2026-08-10

Last updated on: 2026-08-10

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: watchdog: pretimeout: Fix UAF in watchdog_unregister_governor() When a watchdog governor is unregistered, it updates existing watchdog devices that were using this governor by falling back to `default_gov`. If the governor being unregistered is currently set as `default_gov`, the `default_gov` is never cleared. This leads to 2 use-after-free issues: 1. New watchdog devices registered after this point will inherit the dangling `default_gov`. 2. Existing watchdog devices using the unregistered governor will have their `wdd->gov` reassigned to the dangling `default_gov`. Fix the UAF by clearing `default_gov` if it matches the governor being unregistered.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-08-10
Last Modified
2026-08-10
Generated
2026-08-10
AI Q&A
2026-08-10
EPSS Evaluated
N/A
NVD
CVE-2026-68357
EUVD
EUVD-2026-55458

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
linux linux_kernel *

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This is a use-after-free (UAF) vulnerability in the Linux kernel's watchdog subsystem. It occurs when a watchdog governor is unregistered without properly clearing the default governor pointer. This leaves a dangling reference that can be accessed later, causing crashes or potential code execution.

Detection Guidance

This vulnerability is specific to the Linux kernel's watchdog subsystem and requires kernel-level inspection. Check if your kernel version includes the affected code by running: uname -a. If your kernel version is not listed in official advisories for this CVE, it may not be affected. Monitor kernel logs for watchdog-related errors or crashes.

Impact Analysis

If exploited, this could lead to system instability, crashes, or privilege escalation. Systems relying on watchdog timers for stability (servers, embedded devices) may become unresponsive or reboot unexpectedly.

Mitigation Strategies

Apply the latest kernel update from your Linux distribution to patch this vulnerability. If an update is unavailable, consider disabling the watchdog subsystem temporarily until a patch is applied. Restart affected systems after applying updates.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-68357. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart