MEDIUM 6.1

PYSEC-2026-2211

Quick fix

PYSEC-2026-2211 — mistune: upgrade to the fixed version with the command below.

pip install --upgrade 'mistune>=3.3.0'

Details

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.

Are you affected?

Enter the version of the package you're using.

Affected packages

PyPI / mistune

Introduced in: 0 Fixed in: 3.3.0

Fix pip install --upgrade 'mistune>=3.3.0'

References

https://github.com/lepture/mistune/releases/tag/v3.3.0 [ADVISORY]
https://github.com/lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc [FIX]
https://github.com/lepture/mistune/security/advisories/GHSA-8c25-4j27-2rv3 [EVIDENCE]