CVE-2023-25564: Gss-Ntlmssp Project Gss-Ntlmssp

High severity, CVSS 8.2. EPSS: 1.9% chance of exploitation in the next 30 days.

GSS-NTLMSSP is a mechglue plugin for the GSSAPI library that implements NTLM authentication. Prior to version 1.2.0, memory corruption can be triggered when decoding UTF16 strings. The variable `outlen` was not initialized and could cause writing a zero to an arbitrary place in memory if `ntlm_str_convert()` were to fail, which would leave `outlen` uninitialized. This can lead to a denial of service if the write hits unmapped memory or randomly corrupts a byte in the application memory space. This vulnerability can trigger an out-of-bounds write, leading to memory corruption. This vulnerability can be triggered via the main `gss_accept_sec_context` entry point. This issue is fixed in version 1.2.0.

Affected products

• Gss-Ntlmssp Project Gss-Ntlmssp: before 1.2.0 (fixed in 1.2.0)

Published 2023-02-14. Last modified 2026-06-17.