Unity Linux 20.1060e / 20.1070e Security Update: php (UTSA-2026-017556)

high Nessus Plugin ID 313983

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-2026-017556 advisory.

In PHP versions 7.3.x up to and including 7.3.31, 7.4.x below 7.4.25 and 8.0.x below 8.0.12, when running PHP FPM SAPI with main FPM daemon process running as root and child worker processes running as lower- privileged users, it is possible for the child processes to access memory shared with the main process and write to it, modifying it in a way that would cause the root process to conduct invalid memory reads and writes, which can be used to escalate privileges from local unprivileged user to the root user.

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 php package.

See Also

http://www.nessus.org/u?0d75653e

https://nvd.nist.gov/vuln/detail/CVE-2021-21703

http://www.nessus.org/u?f6f7eab9

Plugin Details

Severity: High

ID: 313983

File Name: unity_linux_UTSA-2026-017556.nasl

Version: 1.1

Type: Local

Published: 5/11/2026

Updated: 5/11/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: Medium

Base Score: 6.9

Temporal Score: 5.4

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

CVSS Score Source: CVE-2021-21703

CVSS v3

Risk Factor: High

Base Score: 7

Temporal Score: 6.3

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: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: 5/11/2026

Vulnerability Publication Date: 10/18/2021

Reference Information

CVE: CVE-2021-21703