Unity Linux 20.1070e Security Update: kernel (UTSA-2025-992166)

medium Nessus Plugin ID 280496

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-2025-992166 advisory.

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

ipv6/addrconf: fix a potential refcount underflow for idev

Now in addrconf_mod_rs_timer(), reference idev depends on whether rs_timer is not pending. Then modify rs_timer timeout.

There is a time gap in [1], during which if the pending rs_timer becomes not pending. It will miss to hold idev, but the rs_timer is activated. Thus rs_timer callback function addrconf_rs_timer() will be executed and put idev later without holding idev. A refcount underflow issue for idev can be caused by this.

if (!timer_pending(&idev->rs_timer)) in6_dev_hold(idev);
<--------------[1] mod_timer(&idev->rs_timer, jiffies + when);

To fix the issue, hold idev if mod_timer() return 0.

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?2a02049b

http://www.nessus.org/u?672745d2

https://nvd.nist.gov/vuln/detail/CVE-2023-53189

Plugin Details

Severity: Medium

ID: 280496

File Name: unity_linux_UTSA-2025-992166.nasl

Version: 1.1

Type: local

Published: 12/30/2025

Updated: 12/30/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

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-2023-53189

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/UOS-Server/release, Host/UOS-Server/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 12/30/2025

Vulnerability Publication Date: 9/4/2021

Reference Information

CVE: CVE-2023-53189