TencentOS Server 4: nodejs20 (TSSA-2026:0665)

high Nessus Plugin ID 330799

Synopsis

The remote TencentOS Server 4 host is missing one or more security updates.

Description

The version of Tencent Linux installed on the remote TencentOS Server 4 host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the TSSA-2026:0665 advisory.

Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:

CVE-2026-33630:
A flaw was found in c-ares. A use-after-free / double-free vulnerability exists in the query-completion handling path, where a query callback is invoked while the query is still linked in internal lookup structures. A remote attacker can exploit this via ares_getaddrinfo() over TCP by sending crafted DNS responses that force an EDNS-downgrade retry followed by a connection reset, causing the internal completion handler to access freed memory. This leads to memory corruption and a crash (denial of service), with potential for further impact depending on the allocator and build configuration.

CVE-2026-12151:
Impact:
The undici WebSocket client enforces maxPayloadSize on the cumulative byte count of fragments in a message but does not enforce a limit on the number of fragments. A malicious WebSocket server can stream many small or empty continuation frames that each pass per-frame and cumulative-size validation, collectively causing unbounded memory growth in the client process. The result is memory exhaustion and a denial of service.

Affected applications are those using the undici WebSocket client (new WebSocket(...)) or the WebSocketStream API that can be induced to connect to an attacker-controlled or compromised WebSocket endpoint.

All releases starting at undici 6.17.0 are affected.

Patches:Upgrade to undici >= 6.26.0, >= 7.28.0, or >= 8.5.0.Workarounds:
No workaround is available. The fix must be applied through an upgrade.

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-20260665.xml

Plugin Details

Severity: High

ID: 330799

File Name: tencentos_TSSA_2026_0665.nasl

Version: 1.1

Type: Local

Published: 7/29/2026

Updated: 7/29/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.71

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-33630

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

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

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

CVSS Score Source: CVE-2026-12151

Vulnerability Information

CPE: cpe:/o:tencent:tencentos_server:4, p-cpe:/a:tencent:tencentos_server:nodejs20

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: 7/28/2026

Vulnerability Publication Date: 6/17/2026

Reference Information

CVE: CVE-2026-12151, CVE-2026-33630