SB2026091945 - Memory leak in Linux kernel smb server
Published: September 19, 2026
Breakdown by Severity
- 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.
References
- https://git.kernel.org/stable/c/06c7b1d731bc105a8644f1b70165ba8b9416cbab
- https://git.kernel.org/stable/c/8e2ebc77678832e981adc008d25cd8f67d08ebc4
- https://git.kernel.org/stable/c/a41a98ee16ae038751b6639decadaa3ce15ca18a
- https://git.kernel.org/stable/c/b62b1ebb25f0a19067ed5b1a86036b2dc98be44f
- https://git.kernel.org/stable/c/effcf48d79d8aa53113d8289e140746f25ceb62c