Unity Linux 20.1050e / 20.1060e / 20.1070e Security Update: dnsmasq (UTSA-2026-090253)

low Nessus Plugin ID 348855

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-2026-090253 advisory.

A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By default, a maximum of 150 pending queries can be sent to upstream servers, so there can be at most 150 queries for the same name.
This flaw allows an off-path attacker on the network to substantially reduce the number of attempts that it would have to perform to forge a reply and have it accepted by dnsmasq. This issue is mentioned in the Birthday Attacks section of RFC5452. If chained with CVE-2020-25684, the attack complexity of a successful attack is reduced. The highest threat from this vulnerability is to data integrity.

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 dnsmasq package.

See Also

https://nvd.nist.gov/vuln/detail/CVE-2020-25686

http://www.nessus.org/u?44ee4b1a

http://www.nessus.org/u?5020b1a7

Plugin Details

Severity: Low

ID: 348855

File Name: unity_linux_UTSA-2026-090253.nasl

Version: 1.2

Type: Local

Published: 9/22/2026

Updated: 9/23/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 1.2

Percentile: 0.01

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.2

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

CVSS Score Source: CVE-2020-25686

CVSS v3

Risk Factor: Low

Base Score: 3.7

Temporal Score: 3.2

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

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: 8/6/2026

Vulnerability Publication Date: 1/19/2021

Reference Information

CVE: CVE-2020-25686