Improper locking in Linux kernel - CVE-2026-53274
Published: June 26, 2026
Vulnerability identifier: #VU135479
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-2026-53274
CWE-ID: CWE-667
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 logic flaw in __smc_setsockopt() when copying user-supplied socket option data while holding the socket lock. A local user can pass a userfaultfd-monitored or FUSE-backed memory page as the optval argument to cause a denial of service.
Exploitation can keep the socket lock held indefinitely and, when combined with asynchronous tear-down operations such as shutdown(), can exhaust kernel worker threads and trigger the hung task watchdog.
How to mitigate CVE-2026-53274
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/35a22117839602bb52283de08894c5a7dde92420
- https://git.kernel.org/stable/c/5d27d2ffe487df89ce28fda0410eafa05dbe03a0
- https://git.kernel.org/stable/c/89f6fbe0033c942cb790ffd53ca93a45eeaf1c91
- https://git.kernel.org/stable/c/94d286fa5eedc550d42bcb9c85416af8f77736ff
- https://git.kernel.org/stable/c/a3fdd924d88c30b9f488636ce0e4696012cf5511
- https://git.kernel.org/stable/c/dcd90f42a33e4220385f27b515183d0c91b2fc4a