CVE-2026-59930 (GCVE-0-2026-59930)
Vulnerability from cvelistv5
Published
2026-07-08 16:13
Modified
2026-07-09 13:54
Severity ?
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
  • CWE-1284 - Improper Validation of Specified Quantity in Input
Summary
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.
References
Impacted products
Vendor Product Version
lepture mistune Version: < 3.3.0
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