CVE-2026-59930
Last modified
CVE-2026-59930 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. 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. EPSS estimates a 0.12% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mistune Project | Mistune | < 3.3.0 |
References
- https://github.com/lepture/mistune/security/advisories/GHSA-2hm2-hc3v-44h9Exploit, Third Party Advisory
- https://github.com/lepture/mistune/security/advisories/GHSA-2hm2-hc3v-44h9Exploit, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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