Use-after-free in Linux kernel - CVE-2026-31446
Published: April 24, 2026
Vulnerability identifier: #VU127701
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-31446
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to use-after-free in ext4 update_super_work when racing with filesystem unmount. A local user can trigger error notification activity during unmount to cause a denial of service.
The issue occurs because sysfs notification may access a freed kernfs_node after sysfs teardown during the race.
How to mitigate CVE-2026-31446
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/034053378dd81837fd6c7a43b37ee2e58d4f0b4e
- https://git.kernel.org/stable/c/08b10e6f37fc533a759e9833af0692242e8b3f93
- https://git.kernel.org/stable/c/9449f99ba04f5dd1c8423ad8a90b3651d7240d1d
- https://git.kernel.org/stable/c/c4d829737329f2290dd41e290b7d75effdb2a7ff
- https://git.kernel.org/stable/c/c8fe17a1b308c3d8c703ebfb049b325f844342c3
- https://git.kernel.org/stable/c/c97e282f7bfd0c3554c63d289964a5ca6a1d2ffe
- https://git.kernel.org/stable/c/d15e4b0a418537aafa56b2cb80d44add83e83697