SB20260928365 - Missing Authorization in Linux kernel smb client

Description

This security bulletin contains information about 1 vulnerability.

1) Missing Authorization (CVE-ID: CVE-2026-97564)

CWE-ID: CWE-862 - Missing Authorization

CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a root usermodehelper to process unvetted authority-bearing fields.

The vulnerability exists due to missing authorization validation in cifs.idmap key description handling when invoking request_key(2) with a non-NULL callout. A local user can supply a cifs.idmap key description containing authority-bearing fields to cause a root usermodehelper to process unvetted authority-bearing fields.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/1d3b24b16a0b013792e8f1e3ed060f0b46f537d1
• https://git.kernel.org/stable/c/96751028c0d4dec785709ea3eb0ab38a4f2ded96
• https://git.kernel.org/stable/c/d9d7eeb0cea5b55b82888f443622fd8d4ee064f3
• https://git.kernel.org/stable/c/e5964064e3fbe6325893408faff08ca33de0e2c3