CVE-2026-64391
Last modified
CVE-2026-64391 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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.. EPSS estimates a 0.46% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= f44158485826c076335d6860d35872271a83791d, < a8f5d39971bbad9340d49cd41b0e2da9452a649d; >= f44158485826c076335d6860d35872271a83791d, < 2b4592cea214683de0f2ce6f8c22c097fb0ea1ab; >= f44158485826c076335d6860d35872271a83791d, < 52a56cf53ec834c44ac1b4d16d585f26613ee5ce; >= f44158485826c076335d6860d35872271a83791d, < baa5e094886fffa7e6272edcb5e08be5ce28262c |
| Linux | Linux | 5.15 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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