CVE-2025-40328: Linux

High severity, CVSS 8.8. EPSS: 0.5% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential UAF in smb2_close_cached_fid() find_or_create_cached_dir() could grab a new reference after kref_put() had seen the refcount drop to zero but before cfid_list_lock is acquired in smb2_close_cached_fid(), leading to use-after-free. Switch to kref_put_lock() so cfid_release() is called with cfid_list_lock held, closing that gap.

Affected products

• Linux Linux: from 6.1, before 6.6.117 (fixed in 6.6.117); from 6.7, before 6.12.58 (fixed in 6.12.58); from 6.13, before 6.17.8 (fixed in 6.17.8)

Published 2025-12-09. Last modified 2026-07-30.