CVE-2026-59930
MEDIUM
NVD
CVSS Score
4.3
Severity
MEDIUM
Published
Jul 08, 2026
Vendor
unknown
Description
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the toc plugin and TableOfContents directive generate heading IDs as predictable toc_N values without slugifying the heading text, allowing attacker-controlled id="toc_N" content to collide with generated anchors and redirect same-page navigation, CSS selectors, or JavaScript handlers. This issue is fixed in version 3.3.0.