Unity Linux 20.1050e Security Update: kernel (UTSA-2026-005174)

high Nessus Plugin ID 296964

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-2026-005174 advisory.

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

vrf: use RCU protection in l3mdev_l3_out()

l3mdev_l3_out() can be called without RCU being held:

raw_sendmsg() ip_push_pending_frames() ip_send_skb() ip_local_out()
__ip_local_out() l3mdev_ip_out()

Add rcu_read_lock() / rcu_read_unlock() pair to avoid a potential UAF.

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

http://www.nessus.org/u?63bc171b

http://www.nessus.org/u?76abbd23

https://nvd.nist.gov/vuln/detail/CVE-2025-21791

Plugin Details

Severity: High

ID: 296964

File Name: unity_linux_UTSA-2026-005174.nasl

Version: 1.1

Type: local

Published: 1/27/2026

Updated: 1/27/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

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

CVSS Score Source: CVE-2025-21791

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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: 1/28/2026

Vulnerability Publication Date: 2/27/2025

Reference Information

CVE: CVE-2025-21791