TencentOS Server 3: gssntlmssp (TSSA-2023:0084)

high Nessus Plugin ID 238862

Synopsis

The remote TencentOS Server 3 host is missing one or more security updates.

Description

The version of Tencent Linux installed on the remote TencentOS Server 3 host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the TSSA-2023:0084 advisory.

Package updates are available for TencentOS Server 3 that fix the following vulnerabilities:

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.
CVE-2023-25564:
A flaw was found in GSS-NTLMSSP, a mechglue plugin for the GSSAPI library that implements NTLM authentication. 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 the ntlm_str_convert() fails, which would leave outlen uninitialized. This issue 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, and can be triggered via the main gss_accept_sec_context entry point.
CVE-2023-25565:
A flaw was found in GSS-NTLMSSP, a mechglue plugin for the GSSAPI library that implements NTLM authentication. 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 issue will likely trigger an assertion failure in free, causing a denial of service.
CVE-2023-25566:
A flaw was found in GSS-NTLMSSP, a mechglue plugin for the GSSAPI library that implements NTLM authentication. A memory leak can be triggered when parsing usernames, triggering 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. This flaw allows an attacker to leak memory via the main gss_accept_sec_context entry point, potentially causing a denial of service.
CVE-2023-25567:
A flaw was found in GSS-NTLMSSP, a mechglue plugin for the GSSAPI library that implements NTLM authentication. It has an out-of-bounds read when decoding target information. The length of the av_pair is not checked properly for two of the elements, which can trigger an out-of-bounds read via the main gss_accept_sec_context entry point and could cause a denial of service if the memory is unmapped.

Tenable has extracted the preceding description block directly from the Tencent Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://mirrors.tencent.com/tlinux/errata/tssa-20230084.xml

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-25563

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-25564

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-25565

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-25566

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-25567

Plugin Details

Severity: High

ID: 238862

File Name: tencentos_TSSA_2023_0084.nasl

Version: 1.1

Type: local

Published: 6/16/2025

Updated: 6/16/2025

Supported Sensors: Nessus

Vulnerability Information

CPE: cpe:/o:tencent:tencentos_server:3, p-cpe:/a:tencent:tencentos_server:gssntlmssp

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/etc/os-release, Host/TencentOS/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 6/14/2023

Vulnerability Publication Date: 6/14/2023