Security Advisory
CVE-2026-64391
9.8
CRITICAL
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: use opener credentials for ADS I/O
Alternate data streams are stored as xattrs. Unlike regular file I/O,
their read and write paths therefore call VFS xattr helpers which recheck
inode permissions and LSM policy using the current task credentials.
Run ADS I/O with the credentials captured when the SMB handle was opened.
Published Date
July 25, 2026
Official Source
NIST NVD Advisory