Quadratic runtime when parsing Markdown in comrak

{
  "id": "c4e1091780d7a16506e2f8cc642d786b8b4a622f3abcf68fcb6a31ebf1978492",
  "url": "https://osv.dev/vulnerability/CVE-2023-28626",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Quadratic runtime when parsing Markdown in comrak",
    "summary": "comrak is a CommonMark + GFM compatible Markdown parser and renderer written in rust. A range of quadratic parsing issues are present in Comrak. These can be used to craft denial-of-service attacks on services that use Comrak to parse Markdown. This issue has been addressed in version 0.17.0. Users are advised to upgrade. There are no known workarounds for this vulnerability. This issue is also tracked as `GHSL-2023-047`",
    "evidence": "osv:CVE-2023-28626",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2023-28626",
      "aliases": [
        "CVE-2023-28626",
        "GHSA-8hqf-xjwp-p67v"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/kivikakk/comrak",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "aad5b0544ffbc07feb18f4fed5adb91fb7c80763"
                },
                {
                  "fixed": "ce795b7f471b01589f842dc09af38b025701178d"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:comrak_project:comrak:*:*:*:*:*:rust:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.17.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "ce795b7f471b01589f842dc09af38b025701178d"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "0.16.0",
            "0.15.0",
            "0.14.0",
            "0.13.2",
            "0.13.1",
            "0.13.0",
            "0.12.1",
            "0.12.0",
            "0.11.0",
            "0.10.1",
            "0.10.1-rc.1",
            "0.10.0",
            "0.9.1",
            "0.9.0",
            "0.8.2",
            "0.8.1",
            "0.8.0",
            "0.7.1",
            "0.7.0",
            "0.6.2",
            "0.6.1",
            "0.6.0",
            "0.5.1",
            "0.5.0",
            "0.4.4",
            "0.4.3",
            "0.4.2",
            "0.4.1",
            "0.4.0",
            "0.3.1",
            "0.3.0",
            "0.2.14",
            "0.2.13",
            "0.2.12",
            "0.2.11",
            "0.2.10",
            "0.2.9",
            "0.2.8",
            "0.2.7",
            "0.2.6",
            "0.2.5",
            "0.2.4",
            "0.2.3",
            "0.2.2",
            "0.2.1",
            "0.2.0",
            "0.1.9",
            "0.1.8",
            "0.1.7",
            "0.1.6",
            "0.1.5",
            "0.1.4",
            "0.1.3",
            "0.1.2",
            "0.1.1",
            "0.1.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-28626.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:40.435710363Z",
      "provider": "osv",
      "references": [
        "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OUYME2VA555X6567H7ORIJQFN4BVGT6N/",
        "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PTWZWCT7KCX2KTXTLPUYZ3EHOONG4X46/",
        "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VQ3UBC7LE4VPCMZBTADIBL353CH7CPVV/",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/28xxx/CVE-2023-28626.json",
        "https://github.com/kivikakk/comrak/security/advisories/GHSA-8hqf-xjwp-p67v",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-28626",
        "https://github.com/kivikakk/comrak/commit/ce795b7f471b01589f842dc09af38b025701178d"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-400"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/28xxx/CVE-2023-28626.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-28626",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 507957,
  "published_at": "2023-03-28T20:14:27.217+00:00"
}