CVE-2025-66400

MEDIUM

mdast-util-to-hast <13.2.1 - Info Disclosure

Title source: llm
STIX 2.1

Description

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.

Scores

CVSS v3 5.3
EPSS 0.0008
EPSS Percentile 22.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-915 CWE-20
Status published
Products (2)
npm/mdast-util-to-hast 13.0.0 - 13.2.1npm
unifiedjs/mdast-util-to-hast 13.0.0 - 13.2.1
Published Dec 01, 2025
Tracked Since Feb 18, 2026