SB2026091945 - Memory leak in Linux kernel smb server



SB2026091945 - Memory leak in Linux kernel smb server

Published: September 19, 2026

Security Bulletin ID SB2026091945
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Partial DoS

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Memory leak (CVE-ID: CVE-2026-90169)

CWE-ID: CWE-401 - Missing release of memory after effective lifetime

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to a memory leak in ksmbd preauthentication session handling when a client disconnects after sending a binding NTLM negotiate request and before sending an authenticate request. A remote attacker can initiate an SMB3.1.1 multichannel binding negotiation and disconnect before authentication completes to cause a denial of service.


Remediation

Install update from vendor's website.