CVE-2025-68142

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/facelessuser/pymdown-extensions/commit/b50d15a56850ed1408a284bba81cc019c6bd72e8	Patch
https://github.com/facelessuser/pymdown-extensions/security/advisories/GHSA-r6h4-mm7h-8pmq	Exploit Patch Vendor Advisory
https://pypi.org/project/pymdown-extensions/10.16.1	Product Release Notes

Configurations

Configuration 1 (hide)

cpe:2.3:a:facelessuser:pymdown_extensions:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2025-12-16 18:16

Updated : 2026-02-03 18:56

NVD link : CVE-2025-68142

Mitre link : CVE-2025-68142

CVE.ORG link : CVE-2025-68142

JSON object : View

Products Affected

facelessuser

pymdown_extensions

CWE

CWE-1333

Inefficient Regular Expression Complexity

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