Time-of-check Time-of-use (TOCTOU) Race Condition in Linux kernel - CVE-2026-64112
Published: July 20, 2026
Vulnerability identifier: #VU138528
CSH Severity: Low
CVSS v4.0: 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/E:U/U:Clear
CVE-ID: CVE-2026-64112
CWE-ID: CWE-367
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 a time-of-check time-of-use race condition in the rbd lock_dwork handling in drivers/block/rbd.c when unmapping an image while exclusive lock work is being queued. A local user can trigger image unmap operations during concurrent I/O activity to cause a denial of service.
The issue can result in lock acquisition work executing after device and image release operations have freed or reset internal state.
How to mitigate CVE-2026-64112
Install security update from vendor's repository.