Mistune toc / TableOfContents directive: heading IDs use predictable `toc_N` numbering with no slugification, allowing collision with attacker-controlled `id="toc_N"` content
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 4.3epss 0.1%
exploitation probability
0.1%top 96% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Affected products
lepture · mistune