CVE-2026-64393

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: run set info with opener credentials SMB2 SET_INFO handlers call path-based VFS helpers after checking the access mask granted to the SMB handle. Those helpers perform their owner, inode permission and LSM checks using the current ksmbd worker credentials. Run the complete SET_INFO dispatch with the credentials captured when the handle was opened. This also removes the separate security information credential setup and keeps all SET_INFO classes under one credential scope. Direct override_creds() is used because it can nest with the request credential overrides already used by rename and link helpers.

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EPSS — Exploit Prediction

0.0022

Probability of exploitation

0.12%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/0ce682867fd506f61f40c76bde7e4205bde34e87 https://git.kernel.org/stable/c/20ee516a62989a8d505ee432f9e59525ea23984e https://git.kernel.org/stable/c/5cbabf3a71575cd31bc7785d92d4ab42338a654b https://git.kernel.org/stable/c/8cc9ec711f5255167247a9ab6a7179b787426ed7 https://git.kernel.org/stable/c/b35afd5cf8fab236ef21117e42ee45691d4ffa7b https://git.kernel.org/stable/c/b383bcad3d2fe634b26efbce53e22bbb5753a520

Frequently Asked Questions

What is CVE-2026-64393? +

In the Linux kernel, the following vulnerability has been resolved: ksmbd: run set info with opener credentials SMB2 SET_INFO handlers call path-based VFS helpers after checking the access mask granted to the SMB handle. Those helpers perform their owner, inode permission and LSM checks using the current ksmbd worker credentials. Run the complete SET_INFO dispatch with the credentials captured when the handle was opened. This also removes the separate security information credential setup and keeps all SET_INFO classes under one credential scope. Direct override_creds() is used because it can nest with the request credential overrides already used by rename and link helpers.

How do I check if I'm vulnerable to CVE-2026-64393? +

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.