CVE-2026-49825 (GCVE-0-2026-49825)

Vulnerability from cvelistv5 – Published: 2026-08-20 14:42 – Updated: 2026-08-21 16:41
VLAI
Title
lxml: javascript: URL bypass in Cleaner via xlink:href
Summary
lxml is a library for processing XML and HTML in the Python language. Prior to 6.1.1, link attributes in ``lxml.html.defs.link_attrs`` were missing ``xlink:href``, which can be used for URL bypass attacks in embedded SVG/MathML/etc. content. This vulnerability was fixed in lxml 6.1.1 and lxml_html_clean 0.4.5.
Severity
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-21 16:41 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-184 - Incomplete List of Disallowed Inputs
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7771 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
lxml lxml Affected: < 6.1.1
guessed Create a notification for this product.
fedora-python lxml_html_clean Affected: < 0.4.5
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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