CVE-2026-74521
ksmbd: use memcmp() to compare ClientGUIDs
CVSS Score
9.1
EPSS Score
0.3%
EPSS Percentile
25th
In the Linux kernel, the following vulnerability has been resolved: ksmbd: use memcmp() to compare ClientGUIDs ClientGUID is a fixed-size binary value and can contain embedded NUL bytes. strncmp() stops comparing at the first NUL byte, so different ClientGUID values can incorrectly be treated as equal. Use memcmp() in SMB3 multichannel session binding and FSCTL_VALIDATE_NEGOTIATE_INFO to compare all SMB2_CLIENT_GUID_SIZE bytes.
| Vendor | linux |
| Product | linux |
| Ecosystems | |
| Industries | Technology |
| Published | Aug 15, 2026 |
| Last Updated | Sep 21, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Affected Versions
Linux / Linux
e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < ba2a5b66f1d414eb8403d655f8813783892cfc85 e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < a386c83043015a703e227775f778e40343f45911 e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < d535363299822c5caa543787b21bd5cfa3e41949 e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < e8bb506e6ef749ac0336f3e579d8d02396b7d832
Linux / Linux
5.15
References
git.kernel.org: https://git.kernel.org/stable/c/ba2a5b66f1d414eb8403d655f8813783892cfc85 git.kernel.org: https://git.kernel.org/stable/c/a386c83043015a703e227775f778e40343f45911 git.kernel.org: https://git.kernel.org/stable/c/d535363299822c5caa543787b21bd5cfa3e41949 git.kernel.org: https://git.kernel.org/stable/c/e8bb506e6ef749ac0336f3e579d8d02396b7d832