Unity Linux 20.1050a / 20.1060a / 20.1070a Security Update: pcs (UTSA-2026-005316)

high Nessus Plugin ID 298429

Synopsis

The Unity Linux host is missing one or more security updates.

Description

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-005316 advisory.

Rack is a modular Ruby web server interface. In versions prior to 2.2.19, 3.1.17, and 3.2.2, `Rack::Multipart::Parser` buffers the entire multipart preamble (bytes before the first boundary) in memory without any size limit. A client can send a large preamble followed by a valid boundary, causing significant memory use and potential process termination due to out-of-memory (OOM) conditions. Remote attackers can trigger large transient memory spikes by including a long preamble in multipart/form-data requests. The impact scales with allowed request sizes and concurrency, potentially causing worker crashes or severe slowdown due to garbage collection. Versions 2.2.19, 3.1.17, and 3.2.2 enforce a preamble size limit (e.g., 16 KiB) or discard preamble data entirely. Workarounds include limiting total request body size at the proxy or web server level and monitoring memory and set per-process limits to prevent OOM conditions.

Tenable has extracted the preceding description block directly from the Unity 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 pcs package.

Plugin Details

Severity: High

ID: 298429

File Name: unity_linux_UTSA-2026-005316.nasl

Version: 1.1

Type: local

Family: Unity Linux Local Security Checks

Published: 2/10/2026

Updated: 2/10/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

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-2025-61770

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

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/UOS-Server/release, Host/UOS-Server/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 2/10/2026

Vulnerability Publication Date: 10/7/2025

Reference Information

CVE: CVE-2025-61770

Detections

Analytics