CVE-2025-66400 (GCVE-0-2025-66400)
Vulnerability from cvelistv5
Published
2025-12-01 22:17
Modified
2025-12-02 15:34
Severity ?
6.9 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-20 - Improper Input Validation
  • CWE-915 - Improperly Controlled Modification of Dynamically-Determined Object Attributes
Summary
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.
References
Impacted products
Vendor Product Version
syntax-tree mdast-util-to-hast Version: >= 13.0.0, < 13.2.1
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