CVE-2026-59923: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in lepture mistune
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, HTMLRenderer.safe_url() does not block percent-encoded javascript URIs, allowing attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version 3.3.0.
CVE-2026-59923: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in lepture mistune
Description
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, HTMLRenderer.safe_url() does not block percent-encoded javascript URIs, allowing attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version 3.3.0.
CVSS v3.1
Score 6.1medium
Weaknesses
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-07T18:20:06.125Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4e7ad5c9d9e3dbe36a7dee
Added to database: 07/08/2026, 16:29:09 UTC
Last updated: 07/08/2026, 16:29:09 UTC
Views: 1
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