CVE-2025-68142 LOW

CVE-2025-68142: PyMdown Extensions has ReDOS bug in Figure Capture extension

Vendor Facelessuser
Product pymdown-extensions
Weakness CWE-1333
Published December 16, 2025
Last update December 17, 2025

CVSS base score

2.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U

What the vulnerability does

01Description

PyMdown Extensions is a set of extensions for the `Python-Markdown` markdown project. Versions prior to 10.16.1 have a ReDOS bug found within the figure caption extension (`pymdownx.blocks.caption`). In systems that take unchecked user content, this could cause long hanges when processing the data if a malicious payload was crafted. This issue is patched in Release 10.16.1. As a workaround, those who process unknown user content without timeouts or other safeguards in place to prevent really large, malicious content being aimed at systems may avoid the use of `pymdownx.blocks.caption` until they're able to upgrade.

Key dates

02Disclosure timeline

December 16, 2025 CVE published
December 17, 2025 Record updated