SB2026090594 - Improper locking in Linux kernel fuse
Published: September 5, 2026
Security Bulletin ID
SB2026090594
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Partial DoS
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper locking (CVE-ID: CVE-2026-80855)
CWE-ID: CWE-667 - Improper Locking
CVSSv4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper locking in fuse_open() in fs/fuse/file.c when fuse_dax_break_layouts() fails after a signal interrupts the wait for busy DAX pages to drain during an O_TRUNC open of a DAX-enabled file. A local user can trigger the affected open operation to cause a denial of service.
The stale lock can stall later faults or truncates on the same file.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/1b04d80a27d317064cce2307472f5bef9975bc50
- https://git.kernel.org/stable/c/1d3e701cda2f41d48aa721b3ebefbe0fbf8d74da
- https://git.kernel.org/stable/c/7288c279ddbd654a06c82118c1a3f5570c1807f0
- https://git.kernel.org/stable/c/776e85fda752f9a15e0f82dec42ecacd12a9bd94
- https://git.kernel.org/stable/c/a61524da59a2f5ac9c8de23ff98b30da769ab144
- https://git.kernel.org/stable/c/a927f1867e61b78f39f9da0bbba3c98c2ca151fe
- https://git.kernel.org/stable/c/dcf30a56624c2a0cfab1bada5b1ca8cc0c02f010
- https://git.kernel.org/stable/c/e981474d7bf1457da12404e169ea147d2c8ecea7