CVE-2026-64391
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 Jul 25, 2026
- CVSS 9.8 critical
- 0.5% chance of exploitation in the next 30 days (EPSS)
- A fix is available