MGASA-2021-0246 - Updated python-lxml packages fix a security vulnerability

Publication date: 13 Jun 2021
URL: https://advisories.mageia.org/MGASA-2021-0246.html
Type: security
Affected Mageia releases: 7, 8
CVE: CVE-2021-28957

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 (CVE-2021-28957).

References:
- https://bugs.mageia.org/show_bug.cgi?id=28983
- https://lists.fedoraproject.org/archives/list/[email protected]/thread/3C2R44VDUY7FJVMAVRZ2WY7XYL4SVN45/
- https://www.debian.org/security/2021/dsa-4880
- https://ubuntu.com/security/notices/USN-4896-1
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28957

SRPMS:
- 8/core/python-lxml-4.6.3-1.mga8
- 7/core/python-lxml-4.3.0-1.3.mga7