cvedb.io
CVE-2026-44899
MEDIUM · CVSS 4.7
EPSS exploitation probability: 0%
Published 2026-05-26T21:16:39.953 · Last modified 2026-06-17T10:51:30.283

Summary

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the Image directive plugin validates the :width: and :height: options with a regex compiled as _num_re = re.compile(r"^\d+(?:\.\d*)?"). When the validated value is not a plain integer, render_block_image() inserts it directly into a style="width:...;" or style="height:...;" attribute. Because the value was accepted by the prefix-only regex, any CSS after the leading digits reaches the style= attribute verbatim and without escaping. This vulnerability is fixed in 3.2.1.

Affected products

mistune_project — mistune

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.