Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_admonition() in src/mistune/directives/admonition.py concatenates the Admonition directive :class: option into the HTML class attribute without escaping, allowing attribute injection and cross-site scripting even when HTMLRenderer escape mode is enabled. This issue is fixed in version 3.2.1.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/lepture/mistune/commit/a3cb6e5655308797e8be021d6c7b5bab13cbace2 Patch
- https://github.com/lepture/mistune/security/advisories/GHSA-g97x-gvcm-x72h Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 5.3 · mistune_projectNVD modified 2026-10-25 17:10
Affected (CPE criteria) 1
cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*