CVE-2026-86432

commonmark versions from 2.0.0 before 2.8.4 contain a denial of service vulnerability in XmlRenderer that emits depth-proportional indentation for every XML tag. Attackers can provide deeply nested Markdown or AST structures to cause quadratic memory consumption and output amplification, exhausting server resources.

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/thephpleague/commonmark/security/advisories/GHSA-mj63-m3rc-8ppr
https://www.vulncheck.com/advisories/commonmark-2.0.0-before-2.8.4-denial-of-service-via-xml

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-07 13:20

Updated : 2026-09-10 16:18

NVD link : CVE-2026-86432

Mitre link : CVE-2026-86432

CVE.ORG link : CVE-2026-86432

JSON object : View

Products Affected

No product.

CWE

CWE-405

Asymmetric Resource Consumption (Amplification)

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