Cross-site Scripting (XSS) Affecting python39-pyyaml package, versions <0:5.4.1-1.module+el8.5.0+10613+59a13ec4


Severity

Recommended
0.0
medium
0
10

Based on CentOS security rating.

Threat Intelligence

EPSS
0.53% (67th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications

Snyk Learn

Learn about Cross-site Scripting (XSS) vulnerabilities in an interactive lesson.

Start learning
  • Snyk IDSNYK-CENTOS8-PYTHON39PYYAML-2130537
  • published26 Jul 2021
  • disclosed21 Mar 2021

Introduced: 21 Mar 2021

CVE-2021-28957  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Centos:8 python39-pyyaml to version 0:5.4.1-1.module+el8.5.0+10613+59a13ec4 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python39-pyyaml package and not the python39-pyyaml package as distributed by Centos. See How to fix? for Centos:8 relevant fixed versions and status.

An XSS vulnerability was discovered in python-lxml's clean module versions before 4.6.3. When disabling the safe_attrs_only and forms arguments, the Cleaner class does not remove the formaction attribute allowing for JS to bypass the sanitizer. A remote attacker could exploit this flaw to run arbitrary JS code on users who interact with incorrectly sanitized HTML. This issue is patched in lxml 4.6.3.

CVSS Base Scores

version 3.1