Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098689)

medium Nessus Plugin ID 340263

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-2026-098689 advisory.

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

net_sched: sch_sfq: reject invalid perturb period

Gerrard Tai reported that SFQ perturb_period has no range check yet, and this can be used to trigger a race condition fixed in a separate patch.

We want to make sure ctl->perturb_period * HZ will not overflow and is positive.


tc qd add dev lo root sfq perturb -10 # negative value : error Error: sch_sfq: invalid perturb period.

tc qd add dev lo root sfq perturb 1000000000 # too big : error Error: sch_sfq: invalid perturb period.

tc qd add dev lo root sfq perturb 2000000 # acceptable value tc -s -d qd sh dev lo qdisc sfq 8005: root refcnt 2 limit 127p quantum 64Kb depth 127 flows 128 divisor 1024 perturb 2000000sec Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 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

https://nvd.nist.gov/vuln/detail/CVE-2025-38193

http://www.nessus.org/u?bd07dde6

http://www.nessus.org/u?f1c5003e

Plugin Details

Severity: Medium

ID: 340263

File Name: unity_linux_UTSA-2026-098689.nasl

Version: 1.1

Type: Local

Published: 8/26/2026

Updated: 8/26/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.35

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-2025-38193

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: 8/10/2026

Vulnerability Publication Date: 7/4/2025

Reference Information

CVE: CVE-2025-38193