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VULNERABILITIES

CVE-2026-59929 Details

Description

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url filter in src/mistune/renderers/html.py blocks only javascript:, vbscript:, file:, and data: schemes, allowing legacy or chained schemes such as feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0.

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: [email protected]CVSS-B:6.1 MEDIUMVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://github.com/lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc [email protected]Patch
https://github.com/lepture/mistune/releases/tag/v3.3.0 [email protected]Release Notes
https://github.com/lepture/mistune/security/advisories/GHSA-qfrw-5rxm-mhh2 [email protected]ExploitThird Party Advisory

Weakness Enumeration

CWE-IDCWE NameSource
CWE-184Incomplete List of Disallowed Inputs[email protected]
CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')[email protected]

Affected Products

ProductVersions
mistune project mistune
< 3.3.0

CPE

  • cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.

Change History

3 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-59929
NVD Published Date:
Jul 8, 2026
NVD Last Modified:
Jul 9, 2026
Source:
[email protected]