{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "1.5.0"
              },
              {
                "last_affected": "2.8.3"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "fc33ca12575e98e57cdce7d5f38b2ca5335714b3"
            },
            {
              "fixed": "493a5aa7d65754b73846006eaff9c2c4431a8e2c"
            },
            {
              "fixed": "5703d83ba3da3b2e356a5fedc848ed6d8ffb6529"
            }
          ],
          "repo": "https://github.com/thephpleague/commonmark",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-29pj-957v-52mc"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-692",
      "CWE-79",
      "CWE-86"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71478.json"
  },
  "details": "league/commonmark is a PHP library for parsing and rendering CommonMark Markdown. From 1.5.0 until 2.9.0, the AttributesExtension's href and src unsafe-link filter can be bypassed by embedding control bytes, such as a tab, carriage return, line feed, or leading C0 control character, in a javascript: URL that browsers discard before parsing the scheme, causing the browser to still execute the script even when the unsafe-link filter is enabled. This issue is fixed in 2.9.0.",
  "id": "CVE-2026-71478",
  "modified": "2026-08-09T03:30:22.909331852Z",
  "published": "2026-08-06T20:30:32.045Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/thephpleague/commonmark/releases/tag/2.9.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71478.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/thephpleague/commonmark/security/advisories/GHSA-29pj-957v-52mc"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-71478"
    },
    {
      "type": "FIX",
      "url": "https://github.com/thephpleague/commonmark/commit/493a5aa7d65754b73846006eaff9c2c4431a8e2c"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "league/commonmark: AttributesExtension href/src unsafe-link filter bypass via embedded control bytes"
}