{"id":"CVE-2026-63671","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-63671","generatedAt":"2026-10-28T04:37:30.735Z","title":"Prior to 0.22.1, @nuxtjs/mdc uses parseMarkdown with allowDangerousHtml enabled by default and relies on validateProps, validateProp, and unsafeLinkPrefix to remove executable URLs from untrusted Markdown. validateProp checks only attributes named href…","description":"MDC is a tool to take regular Markdown and write documents interacting deeply with a Vue component. Prior to 0.22.1, @nuxtjs/mdc uses parseMarkdown with allowDangerousHtml enabled by default and relies on validateProps, validateProp, and unsafeLinkPrefix to remove executable URLs from untrusted Markdown. validateProp checks only attributes named href or src, allowing an SVG xlink:href value represented as xLinkHref to retain a javascript: URL that executes in the page origin when selected. The data:text/html denylist entries are also compared against url.protocol, which is only data:, so an iframe src containing data:text/html survives sanitization and executes in an opaque origin when loaded. Plain href javascript: URLs, srcdoc, object, script, and base elements are already blocked, making these two paths specific sibling gaps in the sanitizer. This issue is fixed in version 0.22.1.","published":"2026-09-16T15:17:40.000Z","lastModified":"2026-09-24T21:25:27.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":8.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N"},"cwe":["CWE-79","CWE-184"],"affected":[],"epss":{"score":0.00474,"percentile":0.4078,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.47%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/nuxt-content/mdc/commit/61d636c2983f021288e4fc5c4006733b38cf0d53","source":"security-advisories@github.com"},{"url":"https://github.com/nuxt-content/mdc/pull/491","source":"security-advisories@github.com"},{"url":"https://github.com/nuxt-content/mdc/releases/tag/v0.22.1","source":"security-advisories@github.com"},{"url":"https://github.com/nuxt-content/mdc/security/advisories/GHSA-mxm6-v9r6-r94c","source":"security-advisories@github.com"},{"url":"https://github.com/nuxt-content/mdc/security/advisories/GHSA-mxm6-v9r6-r94c","source":"security-advisories@github.com"},{"url":"https://github.com/nuxt-content/mdc/security/advisories/GHSA-mxm6-v9r6-r94c","source":"security-advisories@github.com"},{"url":"https://github.com/nuxt-content/mdc/security/advisories/GHSA-mxm6-v9r6-r94c","source":"security-advisories@github.com"},{"url":"https://github.com/nuxt-content/mdc/security/advisories/GHSA-mxm6-v9r6-r94c","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-63671","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}