TencentOS Server 2: libpng12 (TSSA-2026:0259)

high Nessus Plugin ID 310933

Synopsis

The remote TencentOS Server 2 host is missing one or more security updates.

Description

The version of Tencent Linux installed on the remote TencentOS Server 2 host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the TSSA-2026:0259 advisory.

Package updates are available for TencentOS Server 2 that fix the following vulnerabilities:

CVE-2026-25646:
LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. Prior to 1.6.55, an out-of-bounds read vulnerability exists in the png_set_quantize() API function. When the function is called with no histogram and the number of colors in the palette is more than twice the maximum supported by the user's display, certain palettes will cause the function to enter into an infinite loop that reads past the end of an internal heap-allocated buffer.
The images that trigger this vulnerability are valid per the PNG specification. This vulnerability is fixed in 1.6.55.

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

Note that Nessus has not tested for this issue 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-20260259.xml

Plugin Details

Severity: High

ID: 310933

File Name: tencentos_TSSA_2026_0259.nasl

Version: 1.1

Type: Local

Published: 4/29/2026

Updated: 4/29/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.6

Temporal Score: 6

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

CVSS Score Source: CVE-2026-25646

CVSS v3

Risk Factor: High

Base Score: 8.1

Temporal Score: 7.3

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

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

CVSS v4

Risk Factor: High

Base Score: 8.3

Threat Score: 7

Threat Vector: CVSS:4.0/E:P

Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N

Vulnerability Information

CPE: p-cpe:/a:tencent:tencentos_server:libpng12, cpe:/o:tencent:tencentos_server:2

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 4/8/2026

Vulnerability Publication Date: 2/10/2026

Reference Information

CVE: CVE-2026-25646

IAVA: 2026-A-0135-S