markdownify allows large headline prefixes such as <h9999999>, which causes memory consumption

NIEDRIG 3.3CVE-2025-46656 · GHSA-7mpr-5m44-h73r · PYSEC-2026-1604 · Published 26/04/2025 · updated 17/06/2026

Kurz gesagt

CVE-2025-46656 ist eine Schwachstelle (NIEDRIG (CVSS 3.3)) in markdownify, markdownify (matthewwithanm).
Wahrscheinlichkeit einer Ausnutzung in den nächsten 30 Tagen (EPSS): 0.22%, höher als bei 12.6% aller Schwachstellen.
Abhilfe: auf 0.14.1 oder neuer aktualisieren.

Package	Affected versions	Patched versions
markdownify PyPI	`< 0.14.1`	`0.14.1`
markdownify matthewwithanm	`< 0.14.1`	`0.14.1`

Description

python-markdownify (aka markdownify) before 0.14.1 allows large headline prefixes such as <h9999999> in addition to <h1> through <h6>. This causes memory consumption.

NVD description

python-markdownify (aka markdownify) before 0.14.1 allows large headline prefixes such as <h9999999> in addition to <h1> through <h6>. This causes memory consumption.

References

nvd.nist.gov/vuln/detail/CVE-2025-46656 · ADVISORY
matthewwithanm/python-markdownify · WEB
matthewwithanm/python-markdownify commit 9595618 · WEB
matthewwithanm/python-markdownify · PACKAGE
matthewwithanm/python-markdownify · WEB
pypi.org/project/markdownify · PACKAGE
GitHub Advisory GHSA-7mpr-5m44-h73r · ADVISORY

Running one of these products? Scan your site to see whether it exposes a vulnerable version.

Scan my site free