Description
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.
Severity (CVSS)
| Base score | 5.3 |
|---|---|
| Severity | Medium |
| Version | CVSS 4.0 |
| Vector | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N |
| Provided by | CNA |
Weaknesses
- CWE-79 — CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected products
| Vendor | Product | Versions |
|---|---|---|
| lepture | mistune | < 3.2.1 |
References
- https://github.com/lepture/mistune/security/advisories/GHSA-g97x-gvcm-x72h (x_refsource_CONFIRM)
- https://github.com/lepture/mistune/commit/a3cb6e5655308797e8be021d6c7b5bab13cbace2 (x_refsource_MISC)
- https://github.com/lepture/mistune/releases/tag/v3.2.1 (x_refsource_MISC)
Generated from the official CVE List on 09 Jul 2026 07:08 UTC.