CVE-2026-49825

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.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/fedora-python/lxml_html_clean/commit/322357ac61c6cf80fcbaba53b4e92e31f3ded9f2
https://github.com/fedora-python/lxml_html_clean/releases/tag/0.4.5
https://github.com/fedora-python/lxml_html_clean/security/advisories/GHSA-4jhm-jv67-739f
https://github.com/lxml/lxml/commit/5927a6d5e851845140975d99b65461e255caaab0
https://github.com/lxml/lxml/releases/tag/lxml-6.1.1
https://github.com/fedora-python/lxml_html_clean/security/advisories/GHSA-4jhm-jv67-739f

Configurations

No configuration.

History

26 Oct 2026, 10:10

Type	Values Removed	Values Added
Summary		(es) lxml es una biblioteca para procesar XML y HTML en el lenguaje Python. Antes de la 6.1.1, los atributos de enlace en ’lxml.html.defs.link_attrs’ carecían de ’xlink:href’, que puede ser utilizado para ataques de omisión de URL en contenido SVG/MathML/etc. incrustado. Esta vulnerabilidad fue corregida en lxml 6.1.1 y lxml_html_clean 0.4.5.

Information

Published : 2026-08-20 15:17

Updated : 2026-10-26 10:10

NVD link : CVE-2026-49825

Mitre link : CVE-2026-49825

CVE.ORG link : CVE-2026-49825

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-184

Incomplete List of Disallowed Inputs

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