CVE-2026-44896

Mistune is a Python Markdown parser with renderers and plugins. In 3.2.0 and realier, in src/mistune/directives/image.py, the render_figure() function concatenates figclass and figwidth options directly into HTML attributes without escaping. This allows attribute injection and XSS even when HTMLRenderer(escape=True) is used, because these values bypass the inline renderer.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/lepture/mistune/security/advisories/GHSA-58cw-g322-p94v	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*

History

28 May 2026, 13:43

Type	Values Removed	Values Added
First Time		Mistune Project mistune Mistune Project
References	~~() https://github.com/lepture/mistune/security/advisories/GHSA-58cw-g322-p94v -~~	() https://github.com/lepture/mistune/security/advisories/GHSA-58cw-g322-p94v - Vendor Advisory
CPE		cpe:2.3:a:mistune_project:mistune::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.1

26 May 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-26 21:16

Updated : 2026-05-28 13:43

NVD link : CVE-2026-44896

Mitre link : CVE-2026-44896

CVE.ORG link : CVE-2026-44896

JSON object : View

Products Affected

mistune_project

mistune

CWE

CWE-79

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

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