{"id":"CVE-2026-84992","summary":"md-editor-v3: XSS via fenced-code language rendering bypass","details":"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","aliases":["GHSA-3rm2-h79c-8qw6"],"modified":"2026-09-19T03:47:36.767923644Z","published":"2026-09-18T17:10:08.497Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84992.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-79"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84992.json"},{"type":"FIX","url":"https://github.com/imzbf/md-editor-v3/commit/2c07360420e74087f5bc63032ab155d93e0a0b10"},{"type":"WEB","url":"https://github.com/imzbf/md-editor-v3/releases/tag/v6.5.4"},{"type":"ADVISORY","url":"https://github.com/imzbf/md-editor-v3/security/advisories/GHSA-3rm2-h79c-8qw6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-84992"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/imzbf/md-editor-v3","events":[{"introduced":"0"},{"fixed":"701a5f868886fce273c279f84ed67b6209931b42"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"0"},{"fixed":"6.5.4"}]}}],"versions":["v6.5.3","v6.5.2","v6.5.1","v6.5.0","v6.4.2","v6.4.1","v6.4.0","v6.3.2","v6.3.1","v6.3.0","v6.2.1","v6.2.0","v6.1.1","v6.1.0","v6.0.1","v6.0.0","v5.8.5","v5.8.4","v5.8.3","v5.8.2","v5.8.1","v5.8.0","v5.7.1","v5.7.0","v5.6.1","v5.6.0","v5.5.1","v5.5.0","v5.4.5","v5.4.4","v5.4.3","v5.4.2","v5.4.1","v5.4.0","v5.3.2","v5.3.1","v5.3.0","v5.2.2","v5.2.1","v5.2.0","v5.1.1","v5.1.0","v5.0.2","v5.0.1","v5.0.0","v4.21.1","v4.21.0","v4.20.4","v4.20.3","v4.20.2","v4.20.1","v4.20.0","v4.19.2","v4.19.1","v4.19.0","v4.18.1","v4.18.0","v4.17.4","v4.17.3","v4.17.2","v4.17.1","v4.17.0","v4.16.9","v4.16.8","v4.16.7","v4.16.6","v4.16.5","v4.16.4","v4.16.3","v4.16.1","v4.16.0","v4.15.6","v4.15.5","v4.15.1","v4.15.0","v4.14.1","v4.14.0","v4.13.5","v4.13.4","v4.13.3","v4.13.2","v4.13.1","v4.13.0","v4.12.4","v4.12.3","v4.12.2","v4.12.1","v4.12.0","v4.11.1","v4.11.0","v4.10.0","v4.9.0","v4.8.2","v4.8.1","v4.8.0","v4.7.0","v4.6.2","v4.6.1","v4.6.0","v4.5.0","v4.4.0","v4.3.0","v4.2.2","v4.2.1","v4.2.0","v4.1.1","v4.1.0","v4.0.4","v4.0.2","v4.0.1","v4.0.0","v3.0.1","v3.0.0","v2.11.0","v2.10.0","v2.9.3","v2.9.2","v2.9.1","v2.9.0","v2.8.1","v2.8.0","v2.7.2","v2.6.0","v2.5.0","v2.4.2","v2.4.1","v2.4.0","v2.3.0","v2.2.1","v2.2.0","v2.1.2","v2.1.1","v2.1.0","v2.0.1","v2.0.0","v2.0.0-beta.11","v2.0.0-beta.10","v2.0.0-beta.9","v2.0.0-beta.7"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-84992.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"}]}