Detections
Analytics

Ubuntu 16.04 ESM / 18.04 LTS / 20.04 LTS : Zsh vulnerabilities (USN-5325-1)

high Nessus Plugin ID 158905

Language:

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS / 21.10 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-5325-1 advisory.

 - In Zsh before 5.8, attackers able to execute commands can regain privileges dropped by the --no-PRIVILEGED option. Zsh fails to overwrite the saved uid, so the original privileges can be restored by executing MODULE_PATH=/dir/with/module zmodload with a module that calls setuid(). (CVE-2019-20044)

 - In zsh before 5.8.1, an attacker can achieve code execution if they control a command output inside the prompt, as demonstrated by a %F argument. This occurs because of recursive PROMPT_SUBST expansion.
 (CVE-2021-45444)

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 packages.

See Also

https://ubuntu.com/security/notices/USN-5325-1

Plugin Details

Severity: High

ID: 158905

File Name: ubuntu_USN-5325-1.nasl

Version: 1.6

Type: local

Agent: unix

Published: 3/14/2022

Updated: 10/16/2023

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

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-2019-20044

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS Score Source: CVE-2021-45444

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:16.04:-:esm, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:zsh, p-cpe:/a:canonical:ubuntu_linux:zsh-common, p-cpe:/a:canonical:ubuntu_linux:zsh-dev, p-cpe:/a:canonical:ubuntu_linux:zsh-static

Required KB Items: Host/cpu, Host/Debian/dpkg-l, Host/Ubuntu, Host/Ubuntu/release

Exploit Ease: No known exploits are available

Patch Publication Date: 3/14/2022

Vulnerability Publication Date: 2/24/2020

Reference Information

CVE: CVE-2019-20044, CVE-2021-45444

USN: 5325-1