PT-2026-61455 · Linux+1 · Linux Kernel+1

CVE-2026-64138

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Published

2026-07-19

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Updated

2026-09-07

CVSS v3.1

8.8

High

VectorAV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)
Description An issue exists in the ksmbd module where the Owner SID and Group SID within the NT Security Descriptor (smb ntsd) retrieved from the parent directory are not properly validated during ACL inheritance. To address this, the smb validate ntsd sid() helper function was introduced to ensure these SIDs are safely validated.
Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

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Related Identifiers

CVE-2026-64138
USN-8593-1
USN-8603-1
USN-8618-1
USN-8663-1
USN-8664-1
USN-8728-1
USN-8729-1

Affected Products

Linux Kernel
Ubuntu