TencentOS Server 3: libXfont2 (TSSA-2026:0901)

high Nessus Plugin ID 341109

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-2026:0901 advisory.

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

CVE-2026-44950:
A flaw was found in the libXfont2 font-server client. This heap buffer overflow vulnerability allows a malicious font server to send specially crafted glyph data. The fs_read_glyphs() function fails to properly validate the total size of the incoming data, leading to an overwrite of memory beyond the intended buffer. If the X server runs as a privileged user, this could result in privilege escalation, allowing an attacker to gain higher access. If the X server runs as an unprivileged user, it could lead to a denial of service, causing the system to crash.

CVE-2026-59679:
A flaw was found in the libXfont2 font-server client. A remote attacker, by operating a malicious font server, could exploit an out-of-bounds read/write vulnerability. This occurs because the client incorrectly handles font data, leading to an out-of-bounds memory access. This can lead to privilege escalation if the X server runs with root privileges, or a denial of service (crash) if it runs as an unprivileged user.

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-20260901.xml

Plugin Details

Severity: High

ID: 341109

File Name: tencentos_TSSA_2026_0901.nasl

Version: 1.1

Type: Local

Published: 8/27/2026

Updated: 8/27/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.13

CVSS v2

Risk Factor: High

Base Score: 7.6

Temporal Score: 5.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-59679

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:tencent:tencentos_server:3, p-cpe:/a:tencent:tencentos_server:libxfont2

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: 8/17/2026

Vulnerability Publication Date: 8/5/2026

Reference Information

CVE: CVE-2026-44950, CVE-2026-59679