CVE-2025-40103: Linux

EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: smb: client: Fix refcount leak for cifs_sb_tlink Fix three refcount inconsistency issues related to `cifs_sb_tlink`. Comments for `cifs_sb_tlink` state that `cifs_put_tlink()` needs to be called after successful calls to `cifs_sb_tlink()`. Three calls fail to update refcount accordingly, leading to possible resource leaks.

Affected products

• Linux Linux: from 3.7, before 5.15.203 (fixed in 5.15.203); from 5.16, before 6.1.158 (fixed in 6.1.158); from 6.2, before 6.6.114 (fixed in 6.6.114); from 6.7, before 6.12.55 (fixed in 6.12.55); from 6.13, before 6.17.5 (fixed in 6.17.5)

Published 2025-10-30. Last modified 2026-06-17.