What’s Vulnerable › Vulnerabilities

CVE-2023-25566: GSS-NTLMSSP vulnerable to memory leak when parsing usernames

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-02-14 · updated 2026-06-17
• Weakness: CWE-401

Description

GSS-NTLMSSP is a mechglue plugin for the GSSAPI library that implements NTLM authentication. Prior to version 1.2.0, a memory leak can be triggered when parsing usernames which can trigger a denial-of-service. The domain portion of a username may be overridden causing an allocated memory area the size of the domain name to be leaked. An attacker can leak memory via the main `gss_accept_sec_context` entry point, potentially causing a denial-of-service. This issue is fixed in version 1.2.0.

Affected products

• gssapi gss-ntlmssp: before 1.2.0 — fixed in 1.2.0

How to fix

Upgrade to a fixed version: gssapi gss-ntlmssp 1.2.0. Check the vendor advisory for mitigations.

References

• https://github.com/gssapi/gss-ntlmssp/commit/8660fb16474054e692a596e9c79670cd4d3954f4
• https://github.com/gssapi/gss-ntlmssp/releases/tag/v1.2.0
• https://github.com/gssapi/gss-ntlmssp/security/advisories/GHSA-mfm4-6g58-jw74
• https://github.com/gssapi/gss-ntlmssp/commit/8660fb16474054e692a596e9c79670cd4d3954f4
• https://github.com/gssapi/gss-ntlmssp/releases/tag/v1.2.0
• https://github.com/gssapi/gss-ntlmssp/security/advisories/GHSA-mfm4-6g58-jw74

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