{"id":"CVE-2026-84992","sourceIdentifier":"security-advisories@github.com","published":"2026-09-18T18:17:17.277","lastModified":"2026-09-24T21:25:27.050","vulnStatus":"Deferred","cveTags":[],"descriptions":[{"lang":"en","value":"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":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"imzbf","product":"md-editor-v3","versions":[{"version":"< 6.5.4","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","baseScore":6.1,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"REQUIRED","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":2.8,"impactScore":2.7}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-18T18:06:01.191667Z","id":"CVE-2026-84992","options":[{"exploitation":"poc"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Primary","description":[{"lang":"en","value":"CWE-79"}]}],"references":[{"url":"https://github.com/imzbf/md-editor-v3/commit/2c07360420e74087f5bc63032ab155d93e0a0b10","source":"security-advisories@github.com"},{"url":"https://github.com/imzbf/md-editor-v3/releases/tag/v6.5.4","source":"security-advisories@github.com"},{"url":"https://github.com/imzbf/md-editor-v3/security/advisories/GHSA-3rm2-h79c-8qw6","source":"security-advisories@github.com"},{"url":"https://github.com/imzbf/md-editor-v3/security/advisories/GHSA-3rm2-h79c-8qw6","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}