CVE-2026-64391 (GCVE-0-2026-64391)
Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-10-30 12:27
VLAI
EPSS
VEX
Title
ksmbd: use opener credentials for ADS I/O
Summary
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.
Severity
9.8 (Critical)
Assigner
References
6 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
f44158485826c076335d6860d35872271a83791d , < 222c4c52c3af2d0f68de31182710df3508a31095
(git)
Affected: f44158485826c076335d6860d35872271a83791d , < 2ad5509dd576ae16d252d4698daf03002f9e0234 (git) Affected: f44158485826c076335d6860d35872271a83791d , < a8f5d39971bbad9340d49cd41b0e2da9452a649d (git) Affected: f44158485826c076335d6860d35872271a83791d , < 2b4592cea214683de0f2ce6f8c22c097fb0ea1ab (git) Affected: f44158485826c076335d6860d35872271a83791d , < 52a56cf53ec834c44ac1b4d16d585f26613ee5ce (git) Affected: f44158485826c076335d6860d35872271a83791d , < baa5e094886fffa7e6272edcb5e08be5ce28262c (git) |
guessed | |
| Linux | Linux |
Affected:
5.15
Unaffected: 0 , < 5.15 (semver) Unaffected: 6.1.191 , ≤ 6.1.* (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.96 , ≤ 6.12.* (semver) Unaffected: 6.18.39 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix) |
guessed |
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