Affected: gssapi gss-ntlmssp

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: Ubuntu:Pro:16.04:LTS: gss-ntlmssp, Ubuntu:Pro:18.04:LTS: gss-ntlmssp, Ubuntu:Pro:20.04:LTS: gss-ntlmssp, Ubuntu:Pro:22.04:LTS: gss-ntlmssp

Phil Turnbull discovered that GSS NTLMSSP may perform out-of-bounds reads when decoding NTLM fields and target information. An attacker could possibly use this issue to cause GSS NTLMSSP to crash, resulting in a denial of service. (CVE-2023-25563, CVE-2023-25567)

Phil Turnbull discovered that GSS NTLMSSP did not properly initialize memory when decoding UTF16 strings. An attacker could possibly use this issue to trigger an out-of-bounds write, resulting in a crash. (CVE-2023-25564)

Phil Turnbull discovered that GSS NTLMSSP did not properly handle memory cleanup. An attacker could possibly use this issue to cause an assertion failure, resulting in a denial of service. (CVE-2023-25565)