node-markdown-it — security advisory

{
  "id": "eec0138efaac4005e7f6eccce4ed7f9475f42d906a6cbcc8b2b7f5d606ac1f78",
  "url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-111766",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "DEBIAN-CVE-2026-111766",
    "summary": "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.",
    "evidence": "osv:DEBIAN-CVE-2026-111766",
    "products": [
      {
        "name": {
          "value": "node-markdown-it",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "22.2.3+dfsg+~12.2.3-2",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-3",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-4",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-5",
            "evidence": "/affected/0/versions"
          }
        ]
      },
      {
        "name": {
          "value": "node-markdown-it",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "22.2.3+dfsg+~12.2.3-2",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-3",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-4",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-5",
            "evidence": "/affected/1/versions"
          }
        ]
      },
      {
        "name": {
          "value": "node-markdown-it",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "22.2.3+dfsg+~12.2.3-2",
            "evidence": "/affected/2/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-3",
            "evidence": "/affected/2/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-4",
            "evidence": "/affected/2/versions"
          },
          {
            "value": "22.2.3+dfsg+~12.2.3-5",
            "evidence": "/affected/2/versions"
          }
        ]
      }
    ],
    "severity": "low",
    "structured": {
      "id": "DEBIAN-CVE-2026-111766",
      "aliases": [
        "DEBIAN-CVE-2026-111766"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "node-markdown-it",
            "purl": "pkg:deb/debian/node-markdown-it?arch=source&distro=bookworm",
            "ecosystem": "Debian:12"
          },
          "versions": [
            "22.2.3+dfsg+~12.2.3-2",
            "22.2.3+dfsg+~12.2.3-3",
            "22.2.3+dfsg+~12.2.3-4",
            "22.2.3+dfsg+~12.2.3-5"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-111766.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "node-markdown-it",
            "purl": "pkg:deb/debian/node-markdown-it?arch=source&distro=trixie",
            "ecosystem": "Debian:13"
          },
          "versions": [
            "22.2.3+dfsg+~12.2.3-2",
            "22.2.3+dfsg+~12.2.3-3",
            "22.2.3+dfsg+~12.2.3-4",
            "22.2.3+dfsg+~12.2.3-5"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-111766.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "node-markdown-it",
            "purl": "pkg:deb/debian/node-markdown-it?arch=source&distro=forky",
            "ecosystem": "Debian:14"
          },
          "versions": [
            "22.2.3+dfsg+~12.2.3-2",
            "22.2.3+dfsg+~12.2.3-3",
            "22.2.3+dfsg+~12.2.3-4",
            "22.2.3+dfsg+~12.2.3-5"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-111766.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        }
      ],
      "modified": "2026-10-27T09:47:40.281724085Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-111766"
      ],
      "references": [
        "https://security-tracker.debian.org/tracker/CVE-2026-111766"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-111766",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 461305,
  "published_at": "2026-10-19T20:17:52.247+00:00"
}