SB20261029210 - Use of Uninitialized Variable in Linux kernel smb server

Description

This security bulletin contains information about 1 vulnerability.

1) Use of Uninitialized Variable (CVE-ID: CVE-2026-99114)

CWE-ID: CWE-457 - Use of Uninitialized Variable

CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote user to disclose residual response-buffer data.

The vulnerability exists due to an uninitialized FileSystemControlFlags field in the Linux kernel ksmbd smb2_get_info_filesystem() function when processing compound SMB requests. A remote user can send a specially crafted compound request that places an FS_CONTROL_INFORMATION response over data left by a discarded earlier response to disclose four bytes of residual response-buffer data.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/03bb4338c3a7c3fc4decf699a35753f0891aab2a
• https://git.kernel.org/stable/c/c0cd3fc6824122014da2b3b0cb7ddeaa2946ec8e
• https://git.kernel.org/stable/c/d8c450ad0d08980b39b08d435efa921086c8b227