{"id":"CVE-2026-84992","revision":"37a85143ecba44c0acb0cfe38494dfd9","records":[{"revision":"37a85143ecba44c0acb0cfe38494dfd9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-84992","aliases":[],"title":"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","state":0,"publishedAt":"2026-09-18T17:10:08.497+00:00","modifiedAt":"2026-09-18T18:06:19.593+00:00","affected":[{"ecosystem":"Vendor product","name":"md-editor-v3","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"imzbf\",\n                    \"product\": \"md-editor-v3\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 6.5.4\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1,"severity":"MEDIUM"}],"references":["https://github.com/imzbf/md-editor-v3/security/advisories/GHSA-3rm2-h79c-8qw6","https://github.com/imzbf/md-editor-v3/commit/2c07360420e74087f5bc63032ab155d93e0a0b10","https://github.com/imzbf/md-editor-v3/releases/tag/v6.5.4"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-84992","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-84992","identifiers":["CVE-2026-84992"]},"retained":false,"historicalAffected":[]}],"coverage":[]}