{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "14.1.0"
                  },
                  {
                    "fixed": "14.3.3"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StringRangeExpression"
              },
              {
                "range": [
                  {
                    "introduced": "15.0.0"
                  },
                  {
                    "fixed": "15.0.3"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StringRangeExpression"
              },
              {
                "range": [
                  {
                    "fixed": "48fbc465812c440020c663f040ab22deaf8f1eca"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "range": [
                  {
                    "fixed": "d99f48839d37af6fd8a2617516c43dab90755503"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "original_tag": "14.3.3",
                "range": [
                  {
                    "fixed": "d372f0d8a68bef0b0acaa68868ce8ae8ba85b384"
                  }
                ],
                "source": "REFERENCES_TAG"
              },
              {
                "original_tag": "15.0.3",
                "range": [
                  {
                    "fixed": "a8c00d474ec9b304fad9b71c16d6fa8b4909279e"
                  }
                ],
                "source": "REFERENCES_TAG"
              }
            ]
          },
          "events": [
            {
              "introduced": "0fe7ccb4b7f30236fb05f623be6924961d296d3d"
            },
            {
              "fixed": "d372f0d8a68bef0b0acaa68868ce8ae8ba85b384"
            },
            {
              "introduced": "157b33bc13649aebecf9ab9b3b8c85ae645abb5a"
            },
            {
              "fixed": "a8c00d474ec9b304fad9b71c16d6fa8b4909279e"
            },
            {
              "fixed": "48fbc465812c440020c663f040ab22deaf8f1eca"
            },
            {
              "fixed": "d99f48839d37af6fd8a2617516c43dab90755503"
            }
          ],
          "repo": "https://github.com/markdown-it/markdown-it",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-gfr2-rv44-r23c"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-400",
      "CWE-407"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/111xxx/CVE-2026-111758.json"
  },
  "details": "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 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.",
  "id": "CVE-2026-111758",
  "modified": "2026-10-22T02:30:22.386104356Z",
  "published": "2026-10-20T20:28:40.677Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/111xxx/CVE-2026-111758.json"
    },
    {
      "type": "FIX",
      "url": "https://github.com/markdown-it/markdown-it/commit/48fbc465812c440020c663f040ab22deaf8f1eca"
    },
    {
      "type": "FIX",
      "url": "https://github.com/markdown-it/markdown-it/commit/d99f48839d37af6fd8a2617516c43dab90755503"
    },
    {
      "type": "WEB",
      "url": "https://github.com/markdown-it/markdown-it/releases/tag/14.3.3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/markdown-it/markdown-it/releases/tag/15.0.3"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/markdown-it/markdown-it/security/advisories/GHSA-gfr2-rv44-r23c"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-111758"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "markdown-it: Quadratic-time rendering of a single multi-line link reference definition with default options (regression since 14.0)"
}