CVE-2026-57530

Description

Milkdown before 7.21.3 contains a stored cross-site scripting vulnerability in the @milkdown/preset-commonmark and @milkdown/components packages that allows attackers with document write access to execute arbitrary JavaScript in the browser context of any user who opens the document or clicks a rendered link. The parseMarkdown runner stores raw URL values from the remark AST as href mark attributes without URL scheme validation, and the ineffective DOMPurify.sanitize call in edit-view.ts treats the bare URL string as a text node and returns it unchanged, allowing javascript: payloads to pass through the link-tooltip preview component and read-only mode anchor elements unmodified.

References

https://www.vulncheck.com/advisories/milkdown-stored-xss-via-javascript-url-in-link-href

https://www.npmjs.com/package/@milkdown/preset-commonmark

https://www.npmjs.com/package/@milkdown/components

https://github.com/Milkdown/milkdown/releases/tag/v7.21.3

https://github.com/Milkdown/milkdown/pull/2410

https://github.com/Milkdown/milkdown/commit/db1ae721854a0ab2f188b83cf8695702966640f1

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4