CVE-2026-64393: ksmbd: run set info with opener credentials
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: run set info with opener credentials
SMB2 SETINFO 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 SETINFO dispatch with the credentials captured when the handle was opened. This also removes the separate security information credential setup and keeps all SETINFO classes under one credential scope.
Direct overridecreds() is used because it can nest with the request credential overrides already used by rename and link helpers.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-64393?
The severity of CVE-2026-64393 is critical with a CVSS score of 9.1.
How do I fix CVE-2026-64393?
To fix CVE-2026-64393, upgrade to the latest version of the Linux kernel that contains the security patch.
What type of systems are affected by CVE-2026-64393?
CVE-2026-64393 affects systems running vulnerable versions of the Linux kernel with ksmbd SMB2 functionality.
What are the potential impacts of exploiting CVE-2026-64393?
Exploitation of CVE-2026-64393 can lead to unauthorized information changes or alterations in the system.
What products are related to CVE-2026-64393?
CVE-2026-64393 is related to the Linux kernel, specifically associated with ksmbd SMB2 SET_INFO handling.