Race condition in Linux kernel - CVE-2026-99111
Published: October 29, 2026
Vulnerability identifier: #VU158482
CSH Severity: Low
CVSS v4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-99111
CWE-ID: CWE-362
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to corrupt file data on an SMB share.
The vulnerability exists due to a race condition in the Linux kernel SMB client's cifs_do_truncate() function when processing concurrent buffered writes and O_TRUNC operations without holding the required locks throughout the flush-truncate-resize sequence. A local user can trigger a buffered write after dirty pages are flushed but before local truncation to cause newly dirtied pages to be silently discarded by cifs_setsize() and truncate_pagecache(), resulting in file data corruption.
Affected software
Linux kernel
How to mitigate CVE-2026-99111
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3