CVE-2026-57530
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…
Does this matter?
Lower severity and a low EPSS score (0.18%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 4.0
- 5.1 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.18% probability · 7th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Source
- disclosure@vulncheck.com
References
- https://github.com/Milkdown/milkdown/commit/db1ae721854a0ab2f188b83cf8695702966640f1
- https://github.com/Milkdown/milkdown/pull/2410
- https://github.com/Milkdown/milkdown/releases/tag/v7.21.3
- https://www.npmjs.com/package/@milkdown/components
- https://www.npmjs.com/package/@milkdown/preset-commonmark
- https://www.vulncheck.com/advisories/milkdown-stored-xss-via-javascript-url-in-link-href
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.