{"cve":"CVE-2026-84992","nvd":{"published":"2026-09-18T18:17:17.277","modified":"2026-09-24T21:25:27.050","status":"Deferred","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","cvss_v4":null,"cvss_v3":{"version":"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},"cwes":["CWE-79"],"references":["https://github.com/imzbf/md-editor-v3/commit/2c07360420e74087f5bc63032ab155d93e0a0b10","https://github.com/imzbf/md-editor-v3/releases/tag/v6.5.4","https://github.com/imzbf/md-editor-v3/security/advisories/GHSA-3rm2-h79c-8qw6","https://github.com/imzbf/md-editor-v3/security/advisories/GHSA-3rm2-h79c-8qw6"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-84992","score":0.00327,"percentile":0.25811,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-3rm2-h79c-8qw6","url":"https://osv.dev/vulnerability/GHSA-3rm2-h79c-8qw6","summary":"md-editor-v3: XSS via fenced-code language rendering bypass","modified":"2026-09-18T17:30:08.398856654Z","packages":[{"ecosystem":"npm","name":"md-editor-v3","purl":"pkg:npm/md-editor-v3","ranges":["<6.5.4"],"fixed":["6.5.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}