CVE-2026-76098 — Mistune has Denial of Service — RecursionError via Excessive Emphasis Markers in Markdown
Mistune is a Python Markdown parser with renderers and plugins. Versions 3.3.0 through 3.3.2 are vulnerable to DoS through deeply nested tokens. HTML rendering creates deeply ne…
Published: 2026-08-24 · CVSS: 7.5 · CVSS 3.1
Mistune is a Python Markdown parser with renderers and plugins. Versions 3.3.0 through 3.3.2 are vulnerable to DoS through deeply nested tokens. HTML rendering creates deeply nested emphasis tokens from consecutive asterisk characters, and recursive rendering in HTMLRenderer.render_token() can exceed Python's recursion limit and raise RecursionError, allowing crafted Markdown to crash a parsing process. This issue is fixed in version 3.3.3
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7