Insufficient Verification of Data Authenticity Affecting mistune package, versions *


Severity

Recommended
low

Based on Debian security rating.

Threat Intelligence

EPSS
0.19% (9th percentile)

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  • Snyk IDSNYK-DEBIAN12-MISTUNE-17896790
  • published9 Jul 2026
  • disclosed8 Jul 2026

Introduced: 8 Jul 2026

CVE-2026-59930  (opens in a new tab)
CWE-345  (opens in a new tab)
CWE-1284  (opens in a new tab)

How to fix?

There is no fixed version for Debian:12 mistune.

NVD Description

Note: Versions mentioned in the description apply only to the upstream mistune package and not the mistune package as distributed by Debian. See How to fix? for Debian:12 relevant fixed versions and status.

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 Base Scores

version 3.1