Unity Linux 20.1050e Security Update: kernel (UTSA-2026-100131)

medium Nessus Plugin ID 336343

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-2026-100131 advisory.

In the Linux kernel, the following vulnerability has been resolved:

netlabel: validate unlabeled address and mask attribute lengths

netlbl_unlabel_addrinfo_get() used the address attribute length to determine whether the attribute data could be read as an IPv4 or IPv6 address, but did not independently validate the corresponding mask attribute length. A crafted Generic Netlink request could therefore provide a valid IPv4/IPv6 address attribute with a shorter mask attribute, which would later be read as a full struct in_addr or struct in6_addr.

NLA_BINARY policy lengths are maximum lengths by default, so use NLA_POLICY_EXACT_LEN() for the unlabeled IPv4/IPv6 address and mask attributes. This rejects short attributes during policy validation and also exposes the exact length requirements through policy introspection.

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 kernel package.

See Also

https://nvd.nist.gov/vuln/detail/CVE-2026-53238

http://www.nessus.org/u?4e2c219b

http://www.nessus.org/u?f491934e

Plugin Details

Severity: Medium

ID: 336343

File Name: unity_linux_UTSA-2026-100131.nasl

Version: 1.1

Type: Local

Published: 8/17/2026

Updated: 8/17/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.75

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

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

CVSS Score Source: CVE-2026-53238

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/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/cpu, Host/UOS-Server/release, Host/UOS-Server/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 8/13/2026

Vulnerability Publication Date: 6/25/2026

Reference Information

CVE: CVE-2026-53238