High 7.5Published Jul 8, 2026

CVE-2026-59925Mistune is a Python Markdown parser with renderers and plugins.

Updated under an hour ago (2026-10-19 09:50 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for mistune_project mistune

Exploited in the last 30 days

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, long sequences of well-formed double-asterisk or triple-asterisk emphasis pairs around a character cause quadratic work in src/mistune/inline_parser.py because the parser scans forward for matching close markers from every potential opening run, allowing denial of service in default Mistune parsing. This issue is fixed in version 3.3.0.

CVSS: 7.5 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-407, CWE-1333
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Analyzed
Record last updated: Jul 9, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

mistune_project mistune mistune_project:mistune	before 3.3.0	NVD

References

https://github.com/lepture/mistune/commit/5de41fb8e527004dbc363e047a3c380c9288c74fpatch
https://github.com/lepture/mistune/releases/tag/v3.3.0release-notes
https://github.com/lepture/mistune/security/advisories/GHSA-4j32-57v6-6g45exploit, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.