CVE-2026-59927

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the Include directive in src/mistune/directives/include.py detects only direct self-includes and not indirect cycles, allowing two markdown files that include each other to trigger unbounded recursion, raise RecursionError, and crash the rendering request. This issue is fixed in version 3.3.0.

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/lepture/mistune/commit/1bef343ade163fc3bb95572b15be720084cdb993	Patch
https://github.com/lepture/mistune/releases/tag/v3.3.0	Release Notes
https://github.com/lepture/mistune/security/advisories/GHSA-8mpj-m6qm-5qr8	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-08 17:17

Updated : 2026-07-09 19:30

NVD link : CVE-2026-59927

Mitre link : CVE-2026-59927

CVE.ORG link : CVE-2026-59927

JSON object : View

Products Affected

mistune_project

mistune

CWE

CWE-674

Uncontrolled Recursion

CWE-755

Improper Handling of Exceptional Conditions

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