CVE-2026-84992

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

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.5.4)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "md-editor-v3", "source": "cna", "vendor": "imzbf"}, "product": "md-editor-v3", "vendor": "imzbf"}], "created": "2026-09-19T14:00:15.412123+00:00", "updated": "2026-09-21T10:04:33.178907+00:00", "vendors": ["imzbf", "imzbf$PRODUCT$md-editor-v3"]}