CVE-2025-40328
Published Dec 9, 2025
Modified Apr 15, 2026
Description
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.
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References
Other References
Frequently Asked Questions
What is CVE-2025-40328? +
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.
How do I check if I'm vulnerable to CVE-2025-40328? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.