Ubuntu 20.04 LTS : PyYAML vulnerability (USN-4940-1)

critical Nessus Plugin ID 149417

Synopsis

The remote Ubuntu host is missing a security update.

Description

The remote Ubuntu 20.04 LTS host has packages installed that are affected by a vulnerability as referenced in the USN-4940-1 advisory.

It was discovered that PyYAML incorrectly handled untrusted YAML files with the FullLoader loader. A remote attacker could possibly use this issue to execute arbitrary code.

Tenable has extracted the preceding description block directly from the Ubuntu 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 python-yaml and / or python3-yaml packages.

See Also

https://ubuntu.com/security/notices/USN-4940-1

Plugin Details

Severity: Critical

ID: 149417

File Name: ubuntu_USN-4940-1.nasl

Version: 1.6

Type: local

Agent: unix

Published: 5/12/2021

Updated: 8/28/2024

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: Critical

Base Score: 10

Temporal Score: 7.4

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

CVSS Score Source: CVE-2020-14343

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

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

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

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:python3-yaml, p-cpe:/a:canonical:ubuntu_linux:python-yaml, cpe:/o:canonical:ubuntu_linux:20.04:-:lts

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

Exploit Ease: No known exploits are available

Patch Publication Date: 5/10/2021

Vulnerability Publication Date: 1/21/2021

Reference Information

CVE: CVE-2020-14343

IAVA: 2021-A-0463

USN: 4940-1