CVE-2024-52595

HTML Cleaner allows crafted scripts in special contexts like svg or math to pass through

State
Published
Severity
7.7 High
Published
Nov 19, 2024
Updated
Nov 20, 2024
Reserved
Nov 14, 2024

Read the record on cve.org

Description

lxml_html_clean is a project for HTML cleaning functionalities copied from `lxml.html.clean`. Prior to version 0.4.0, 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. Users employing the HTML cleaner in a security-sensitive context should upgrade to lxml 0.4.0, which addresses this issue. As a temporary mitigation, users can configure lxml_html_clean with the following settings to prevent the exploitation of this vulnerability. Via `remove_tags`, one may specify tags to remove - their content is moved to their parents' tags. Via `kill_tags`, one may specify tags to be removed completely. Via `allow_tags`, one may restrict the set of permissible tags, excluding context-switching tags like `<svg>`, `<math>` and `<noscript>`.

Scores

CVSSScoreVectorSource
3.17.7 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:HGitHub_M

Weaknesses

  • CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-83 Improper Neutralization of Script in Attributes in a Web Page
  • CWE-184 Incomplete List of Disallowed Inputs

Affected Products

ProductVersions
lxml_html_cleanfedora-python
  • < 0.4.0Affected

References

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