CVE-2023-25565

GSS-NTLMSSP is a mechglue plugin for the GSSAPI library that implements NTLM authentication. Prior to version 1.2.0, an incorrect free when decoding target information can trigger a denial of service. The error condition incorrectly assumes the cb and sh buffers contain a copy of the data that needs to be freed. However, that is not the case. This vulnerability can be triggered via the main gss_accept_sec_context entry point. This will likely trigger an assertion failure in free, causing a denial-of-service. This issue is fixed in version 1.2.0.

Weakness

The product attempts to return a memory resource to the system, but it calls the wrong release function or calls the appropriate release function incorrectly.

Affected Software

Extended Description

This weakness can take several forms, such as:

Potential Mitigations

• Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
• For example, glibc in Linux provides protection against free of invalid pointers.

References

• https://github.com/gssapi/gss-ntlmssp/commit/c16100f60907a2de92bcb676f303b81facee0f64
• https://github.com/gssapi/gss-ntlmssp/releases/tag/v1.2.0
• https://github.com/gssapi/gss-ntlmssp/security/advisories/GHSA-7q7f-wqcg-mvfg