CVE-2026-64391 PUBLISHED

ksmbd: use opener credentials for ADS I/O

Assigner: Linux
Reserved: 19.07.2026 Published: 25.07.2026 Updated: 25.07.2026

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.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to a8f5d39971bbad9340d49cd41b0e2da9452a649d (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 2b4592cea214683de0f2ce6f8c22c097fb0ea1ab (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 52a56cf53ec834c44ac1b4d16d585f26613ee5ce (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to baa5e094886fffa7e6272edcb5e08be5ce28262c (excl.)
  • affected from 0 to 6.12.96 (excl.)
  • affected from 0 to 6.18.39 (excl.)
  • affected from 0 to 7.1.4 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • unaffected from 6.12.96 to 6.12.* (incl.)
  • unaffected from 6.18.39 to 6.18.* (incl.)
  • unaffected from 7.1.4 to 7.1.* (incl.)
  • unaffected from 7.2-rc1 to * (incl.)

References