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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-59925 Detail

Description

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.


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/5de41fb8e527004dbc363e047a3c380c9288c74f 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-4j32-57v6-6g45 GitHub, Inc. Exploit  Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-407 Inefficient Algorithmic Complexity cwe source acceptance level NIST   GitHub, Inc.  
CWE-1333 Inefficient Regular Expression Complexity 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-2026-59925
NVD Published Date:
07/08/2026
NVD Last Modified:
07/09/2026
Source:
GitHub, Inc.