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.

A flaw was found in the Linux kernel's ksmbd component. This vulnerability allows a local attacker to escalate privileges by manipulating Server Message Block (SMB2) SET_INFO operations. The system incorrectly uses the ksmbd worker's credentials instead of the original user's credentials when performing file system checks, potentially bypassing security restrictions and enabling unauthorized actions.

Red Hat Enterprise Linux 10 Not affected kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt Red Hat Hardened Images Not affected erlang27 https://www.cve.org/CVERecord?id=CVE-2026-64393 https://nvd.nist.gov/vuln/detail/CVE-2026-64393 https://lore.kernel.org/linux-cve-announce/2026072528-CVE-2026-64393-200f@gregkh/T