Mistune Math Plugin XSS Escape Bypass_CVE-2026-44708

6.1 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

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.

Basic Information

ID CVE-2026-44708

Source GitHub_M

Published May 26, 2026 at 20:39

Affected Product

Vendor lepture

Product mistune

Version < 3.2.1

Affected Versions lepture mistune < 3.2.1

CWE Classification

CWE-79

References

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    "published": "2026-05-26T20:39:18.990Z",
    "modified": "2026-05-26T20:39:18.990Z",
    "type": "cve",
    "title": "Mistune Math Plugin XSS Escape Bypass",
    "source": "GitHub_M",
    "references": "https://github.com/lepture/mistune/security/advisories/GHSA-8g87-j6q8-g93x\nhttps://github.com/lepture/mistune/releases/tag/v3.2.1",
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