NULL pointer dereference in Gss-ntlmssp - #VU151097
Published: September 18, 2026
Vulnerability identifier: #VU151097
CSH Severity: Low
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-476
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to a null pointer dereference in the NTLMv1 client-challenge extraction in gssntlm_srv_auth() when processing a Type-3 AUTHENTICATE message with a zero-length LM response. A remote attacker can send a specially crafted authentication message to cause a denial of service.
The vulnerable path requires NTLMv1 with extended session security negotiated and an NT response of exactly 24 bytes.
Affected software
Gss-ntlmssp
Remediation
Install security update from vendor's website.
Gss-ntlmssp - update to 1.3.2