Unity Linux 20.1070e Security Update: kernel (UTSA-2025-414666)

high Nessus Plugin ID 267714

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-2025-414666 advisory.

An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped.
However, the handler may not have time to run if the frontend quickly toggles between the states connect and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback.

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.

See Also

http://www.nessus.org/u?1dbc283c

https://nvd.nist.gov/vuln/detail/CVE-2020-29569

Plugin Details

Severity: High

ID: 267714

File Name: unity_linux_UTSA-2025-414666.nasl

Version: 1.1

Type: local

Published: 10/7/2025

Updated: 10/7/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.3

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

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

CVSS Score Source: CVE-2020-29569

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/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: 7/8/2025

Vulnerability Publication Date: 12/15/2020

Reference Information

CVE: CVE-2020-29569