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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-59930 Detail

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

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/lepture/mistune/commit/c4093c4742ed0d10d9332fb8edb455869b7b581b GitHub, Inc. Patch 
https://github.com/lepture/mistune/releases/tag/v3.3.0 GitHub, Inc. Release Notes 
https://github.com/lepture/mistune/security/advisories/GHSA-2hm2-hc3v-44h9 CISA-ADP, GitHub, Inc. Exploit  Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-345 Insufficient Verification of Data Authenticity GitHub, Inc.  
CWE-1284 Improper Validation of Specified Quantity in Input GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-59930
NVD Published Date:
07/08/2026
NVD Last Modified:
07/09/2026
Source:
GitHub, Inc.