GHSA-5jfw-gq64-q45f

Suggest an improvement
Source
https://github.com/advisories/GHSA-5jfw-gq64-q45f
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/11/GHSA-5jfw-gq64-q45f/GHSA-5jfw-gq64-q45f.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-5jfw-gq64-q45f
Aliases
Published
2024-11-19T21:07:59Z
Modified
2025-01-14T16:52:36Z
Severity
  • 7.7 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:H CVSS Calculator
Summary
HTML Cleaner allows crafted scripts in special contexts like svg or math to pass through
Details

Impact

The HTML Parser in lxml does not properly handle context-switching for special HTML tags such as <svg>, <math> and <noscript>. This behavior deviates from how web browsers parse and interpret such tags. Specifically, content in CSS comments is ignored by lxml_html_clean but may be interpreted differently by web browsers, enabling malicious scripts to bypass the cleaning process. This vulnerability could lead to Cross-Site Scripting (XSS) attacks, compromising the security of users relying on lxml_html_clean in default configuration for sanitizing untrusted HTML content.

Patches

Users employing the HTML cleaner in a security-sensitive context should upgrade to lxml 0.4.0, which addresses this issue.

Workarounds

As a temporary mitigation, users can configure lxml_html_clean with the following settings to prevent the exploitation of this vulnerability:

  • remove_tags: Specify tags to remove - their content is moved to their parents' tags.
  • kill_tags: Specify tags to be removed completely.
  • allow_tags: Restrict the set of permissible tags, excluding context-switching tags like <svg>, <math> and <noscript>.

References

Database specific 
{
    "cwe_ids": [
        "CWE-184",
        "CWE-79",
        "CWE-83"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-11-19T21:07:59Z",
    "nvd_published_at": "2024-11-19T22:15:21Z",
    "severity": "HIGH"
}
References

Affected packages

PyPI / lxml-html-clean

Package

Name
lxml-html-clean
View open source insights on deps.dev
Purl
pkg:pypi/lxml-html-clean

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
0.4.0

Affected versions

0.*
0.1.0
0.1.1
0.2.0
0.2.1
0.2.2
0.3.0
0.3.1

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/11/GHSA-5jfw-gq64-q45f/GHSA-5jfw-gq64-q45f.json"