{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:*",
            "extracted_events": [
              {
                "introduced": "1.5.0"
              },
              {
                "fixed": "2.10.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "CPE_RANGE"
            ]
          },
          "events": [
            {
              "introduced": "fc33ca12575e98e57cdce7d5f38b2ca5335714b3"
            },
            {
              "fixed": "d2d1aa8b35e072966c89bc0c66cf926e56767dc4"
            }
          ],
          "repo": "https://github.com/thephpleague/commonmark",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-8rr7-cvq3-gmfh"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-407"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86428.json"
  },
  "details": "commonmark versions from 1.5.0 before 2.10.0 contain a denial of service vulnerability in the AttributesExtension when processing distinctly-named attributes. Attackers can submit Markdown with numerous distinct attribute names to cause quadratic-time attribute merging and filtering, consuming disproportionate CPU resources and preventing legitimate requests from completing.",
  "id": "CVE-2026-86428",
  "modified": "2026-09-11T03:30:18.022905596Z",
  "published": "2026-09-07T12:53:49.235Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86428.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/thephpleague/commonmark/security/advisories/GHSA-8rr7-cvq3-gmfh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-86428"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/commonmark-1.5.0-before-2.10.0-denial-of-service-via-attributes"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "commonmark 1.5.0 before 2.10.0 Denial of Service via Attributes"
}