{"id":"CVE-2026-111758","title":"markdown-it: Quadratic-time rendering of a single multi-line link reference definition with default options (regression since 14.0)","summary":"markdown-it is a Markdown parser. From versions 14.1.0 to before 14.3.3, and 15.0.0 to before 15.0.3, a link reference definition whose label or title is never closed is O(n²) with default options. Continuation lines are pulled lazily wi…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","cwe":["CWE-400","CWE-407","CWE-1046"],"vendor":"markdown-it","product":"markdown-it","affected":["markdown-it >= 14.1.0, < 14.3.3","markdown-it >= 15.0.0, < 15.0.3"],"ssvc":{"exploitation":"poc","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-28T16:39:57.942731Z"},"exploitAvailable":true,"published":"2026-10-20","updated":"2026-10-28","sourceUpdated":"2026-10-28T16:40:33.483Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-111758","references":[{"url":"https://github.com/markdown-it/markdown-it/security/advisories/GHSA-gfr2-rv44-r23c","label":"https://github.com/markdown-it/markdown-it/security/advisories/GHSA-gfr2-rv44-r23c"},{"url":"https://github.com/markdown-it/markdown-it/commit/48fbc465812c440020c663f040ab22deaf8f1eca","label":"https://github.com/markdown-it/markdown-it/commit/48fbc465812c440020c663f040ab22deaf8f1eca"},{"url":"https://github.com/markdown-it/markdown-it/commit/d99f48839d37af6fd8a2617516c43dab90755503","label":"https://github.com/markdown-it/markdown-it/commit/d99f48839d37af6fd8a2617516c43dab90755503"},{"url":"https://github.com/markdown-it/markdown-it/releases/tag/14.3.3","label":"https://github.com/markdown-it/markdown-it/releases/tag/14.3.3"},{"url":"https://github.com/markdown-it/markdown-it/releases/tag/15.0.3","label":"https://github.com/markdown-it/markdown-it/releases/tag/15.0.3"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-111758.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-111758"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2556455"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-111758"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-111758"},{"url":"https://github.com/advisories/GHSA-gfr2-rv44-r23c"}],"tags":["cve.org","exploit-available","csaf","vex","red-hat","ghsa","npm"],"epss":0.00455,"epssPercentile":0.39405,"aliases":["GHSA-gfr2-rv44-r23c"],"ecosystem":"npm","patched":["markdown-it 14.3.3","markdown-it 15.0.3"],"ingestedAt":"2026-10-20T21:19:21.139Z","slug":"CVE-2026-111758","body":"## Overview\n\nmarkdown-it is a Markdown parser. From versions 14.1.0 to before 14.3.3, and 15.0.0 to before 15.0.3, a link reference definition whose label or title is never closed is O(n²) with default options. Continuation lines are pulled lazily with str += lineContent in src/rules_block/reference.ts, and the subsequent charCodeAt and slice calls flatten the V8 cons-string, copying everything collected so far; this runs before the rule decides the definition is invalid. No options are required to trigger it. This issue has been patched in versions 14.3.3 and 15.0.3.\n\n## Affected\n\n- `markdown-it >= 14.1.0, < 14.3.3`\n- `markdown-it >= 15.0.0, < 15.0.3`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-111758)\n\nAffected packages:\n\n- `markdown-it >= 14.1.0, < 14.3.3`\n- `markdown-it >= 15.0.0, < 15.0.3`\n\nPatched in:\n\n- `markdown-it 14.3.3`\n- `markdown-it 15.0.3`\n\nSource: https://github.com/advisories/GHSA-gfr2-rv44-r23c\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · affected: Red Hat Build of Podman Desktop, Red Hat Ceph Storage 9, Red Hat Developer Hub, Red Hat Hardened Images, Red Hat OpenShift AI (RHOAI), Red Hat OpenShift Dev Spaces, … · no fix planned: Red Hat Ceph Storage 9, Red Hat Build of Podman Desktop, Red Hat Developer Hub, Red Hat Hardened Images, … · updated 2026-10-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-111758.json)","depth":"midnight","depthScore":53,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":230738,"id":"CVE-2026-111758","ts":1793207727962,"field":"exploit_available","old":"false","new":"true"}]}