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CVE PROGRAM SOURCE RECORD6.1 Medium

CVE-2026-84992

md-editor-v3: XSS via fenced-code language rendering bypass

Description

md-editor-v3 is a Markdown editor for Vue 3 developed in JSX and TypeScript. Prior to 6.5.4, MdPreview's useMarkdownIt() highlight callback in packages/MdEditor/layouts/Content/composition/useMarkdownIt.ts inserts a fenced-code language value into class and language HTML attributes without escaping or consistently quoting it. Both highlighted and non-highlighted rendering paths reach this return value, while XSSPlugin filters only existing html_block and html_inline tokens before rendering and therefore cannot inspect the renderer-generated HTML. An attacker who can supply Markdown can use crafted fenced-code metadata to execute JavaScript in the application origin when a victim renders it, including as stored cross-site scripting when the host persists the Markdown. This issue is fixed in version 6.5.4

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

imzbf md-editor-v3

  • < 6.5.4affected

References