SB20260425103 - Out-of-bounds read in Linux kernel smb client

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds read (CVE-ID: CVE-2026-31613)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to out-of-bounds read in the SMB client symlink response parser when parsing a crafted symlink error response from an untrusted server. A remote attacker can send a specially crafted SMB response to disclose sensitive information.

The exposed heap bytes are UTF-16-decoded into the symlink target and returned to userspace via readlink(2).

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/781902e069f4ecb6c3b83502f181972c1446110a
• https://git.kernel.org/stable/c/a66ef2e7ed837325c5600f8617d5ee0a0a149fdd
• https://git.kernel.org/stable/c/e0dd90d14cbbf318157ea8e3fb62ee68a28655ed