Unity Linux 20.1070a Security Update: kernel (UTSA-2025-989883)

high Nessus Plugin ID 272960

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-2025-989883 advisory.

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

mm/khugepaged: invoke MMU notifiers in shmem/file collapse paths

Any codepath that zaps page table entries must invoke MMU notifiers to ensure that secondary MMUs (like KVM) don't keep accessing pages which aren't mapped anymore. Secondary MMUs don't hold their own references to pages that are mirrored over, so failing to notify them can lead to page use-after-free.

I'm marking this as addressing an issue introduced in commit f3f0e1d2150b (khugepaged: add support of collapse for tmpfs/shmem pages), but most of the security impact of this only came in commit 27e1f8273113 (khugepaged:
enable collapse pmd for pte-mapped THP), which actually omitted flushes for the removal of present PTEs, not just for the removal of empty page tables.

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.

Plugin Details

Severity: High

ID: 272960

File Name: unity_linux_UTSA-2025-989883.nasl

Version: 1.1

Type: local

Family: Unity Linux Local Security Checks

Published: 11/5/2025

Updated: 11/5/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.3

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

CVSS Score Source: CVE-2022-48991

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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:P/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 Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 11/5/2025

Vulnerability Publication Date: 2/7/2023

Reference Information

CVE: CVE-2022-48991

Detections

Analytics