HIGH 7.5

PYSEC-2026-2210

Quick fix

PYSEC-2026-2210 — 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, a run of closed tilde, equals-sign, or caret marker pairs around a character causes quadratic work in src/mistune/plugins/formatting.py when the strikethrough, mark, or insert plugin scans for matching markers from each possible start position, allowing denial of service through CPU exhaustion. 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/96d0f57f8fe9eeb06bb4cff521962a27d7c402e7 [FIX]
https://github.com/lepture/mistune/security/advisories/GHSA-c8j7-8cv4-2xmq [EVIDENCE]