{"id":"CVE-2026-111766","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-111766","generatedAt":"2026-10-28T01:12:06.383Z","title":"Prior to 14.3.3 and 15.0.3, when the html option or commonmark preset is enabled and the constructs occur inside a paragraph, attacker-controlled Markdown containing repeated unterminated inline HTML comments, processing instructions, declarations, or…","description":"markdown-it is a Markdown parser. Prior to 14.3.3 and 15.0.3, when the html option or commonmark preset is enabled and the constructs occur inside a paragraph, attacker-controlled Markdown containing repeated unterminated inline HTML comments, processing instructions, declarations, or CDATA sections reaches src/rules_inline/html_inline.ts. Its HTML_TAG_RE match searches the remaining suffix for the appropriate terminator; when no terminator is present, parsing advances to the next opener and repeats the match over overlapping input, causing quadratic processing and denial of service through event-loop blocking or an unresponsive browser main thread. HTML blocks and the default HTML-disabled configuration are not affected by these payloads. This issue is fixed in versions 14.3.3 and 15.0.3.","published":"2026-10-19T20:17:52.000Z","lastModified":"2026-10-26T18:17:36.000Z","status":"Awaiting Analysis","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":3.7,"severity":"LOW","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"},"cwe":["CWE-400","CWE-407"],"affected":[],"epss":{"score":0.00428,"percentile":0.36778,"date":"2026-10-26","history":[{"date":"2026-10-20","score":0.0035,"percentile":0.27198}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.43%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-19T20:17:52.000Z","detail":{"score":"3.7","severity":"LOW","publishedAt":"2026-10-19T20:17:52.247Z"},"summary":"New CVE, low severity (CVSS 3.7)."}],"references":[{"url":"https://github.com/markdown-it/markdown-it/commit/928bc8c11ded60181c0e7fc5aa954eec582e8e79","source":"security-advisories@github.com"},{"url":"https://github.com/markdown-it/markdown-it/commit/d99f48839d37af6fd8a2617516c43dab90755503","source":"security-advisories@github.com"},{"url":"https://github.com/markdown-it/markdown-it/releases/tag/14.3.3","source":"security-advisories@github.com"},{"url":"https://github.com/markdown-it/markdown-it/releases/tag/15.0.3","source":"security-advisories@github.com"},{"url":"https://github.com/markdown-it/markdown-it/security/advisories/GHSA-vfgh-jcmw-g37q","source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-111766","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."}