CVE-2023-25563

A flaw was found in GSS-NTLMSSP, a mechglue plugin for the GSSAPI library that implements NTLM authentication. Multiple out-of-bounds reads occur when decoding NTLM fields and can trigger a denial of service. A 32-bit integer overflow condition can lead to incorrect checks of the consistency of the length of internal buffers. Although most applications will error out before accepting a single input buffer of 4GB in length, this issue can happen. This vulnerability can be triggered via the main gss_accept_sec_context entry point if the application allows tokens greater than 4GB in length, leading to a large, up to 65KB, out-of-bounds read, which could cause a denial of service if it reads from unmapped memory.