CVE-2025-66400

mdast-util-to-hast is an mdast utility to transform to hast. From 13.0.0 to before 13.2.1, multiple (unprefixed) classnames could be added in markdown source by using character references. This could make rendered user supplied markdown code elements appear like the rest of the page. This vulnerability is fixed in 13.2.1.

CVSS

No CVSS.

References

Link	Resource
https://github.com/syntax-tree/mdast-util-to-hast/commit/6fc783ae6abdeb798fd5a68e7f3f21411dde7403
https://github.com/syntax-tree/mdast-util-to-hast/commit/ab3a79570a1afbfa7efef5d4a0cd9b5caafbc5d7
https://github.com/syntax-tree/mdast-util-to-hast/security/advisories/GHSA-4fh9-h7wg-q85m

Configurations

No configuration.

History

01 Dec 2025, 23:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-12-01 23:15

Updated : 2025-12-02 17:16

NVD link : CVE-2025-66400

Mitre link : CVE-2025-66400

CVE.ORG link : CVE-2025-66400

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-915

Improperly Controlled Modification of Dynamically-Determined Object Attributes

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