CVE-2026-44708

MEDIUM

Mistune Math Plugin XSS Escape Bypass

Title source: cna
STIX 2.1

Description

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the mistune math plugin renders inline math ($...$) and block math ($$...$$) by concatenating the raw user-supplied content directly into the HTML output without any HTML escaping. This occurs even when the parser is explicitly created with escape=True, which is supposed to guarantee that all user-controlled text is sanitised before reaching the DOM. This vulnerability is fixed in 3.2.1.

References (2)

Core 2
Core References
X_Refsource_Misc x_refsource_misc
https://github.com/lepture/mistune/releases/tag/v3.2.1

Scores

CVSS v3 6.1
EPSS 0.0020
EPSS Percentile 9.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-79
Status published
Products (3)
lepture/mistune < 3.2.1
mistune_project/mistune < 3.2.1
pypi/mistune 0 - 3.2.0PyPI
Published May 26, 2026
Tracked Since May 27, 2026