Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098959)

high Nessus Plugin ID 340185

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-2026-098959 advisory.

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

net: rose: convert 'use' field to refcount_t

The 'use' field in struct rose_neigh is used as a reference counter but lacks atomicity. This can lead to race conditions where a rose_neigh structure is freed while still being referenced by other code paths.

For example, when rose_neigh->use becomes zero during an ioctl operation via rose_rt_ioctl(), the structure may be removed while its timer is still active, potentially causing use-after-free issues.

This patch changes the type of 'use' from unsigned short to refcount_t and updates all code paths to use rose_neigh_hold() and rose_neigh_put() which operate reference counts atomically.

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-2025-39826

http://www.nessus.org/u?1fa4c8de

http://www.nessus.org/u?b489b097

Plugin Details

Severity: High

ID: 340185

File Name: unity_linux_UTSA-2026-098959.nasl

Version: 1.1

Type: Local

Published: 8/26/2026

Updated: 8/26/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 57.16

CVSS v2

Risk Factor: Medium

Base Score: 6

Temporal Score: 4.4

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

CVSS Score Source: CVE-2025-39826

CVSS v3

Risk Factor: High

Base Score: 7

Temporal Score: 6.1

Vector: CVSS:3.0/AV:L/AC:H/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: 8/10/2026

Vulnerability Publication Date: 9/16/2025

Reference Information

CVE: CVE-2025-39826