{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "4.5.0-beta.1"
              },
              {
                "fixed": "4.5.10"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "5a8ab0a3e62a8825e28bb74c1760ba6488d20c97"
            },
            {
              "fixed": "f80b1ba92e63c3da771b405b9100f5c9abda909f"
            }
          ],
          "repo": "https://github.com/mastodon/mastodon",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-chgx-jx3p-rf73"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-347"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46349.json"
  },
  "details": "Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing attackers to re-arrange a valid signed JSON-LD activity from a third-party actor to have it processed differently. This vulnerability is fixed in 4.5.10, 4.4.17, and 4.3.23.",
  "id": "CVE-2026-46349",
  "modified": "2026-07-15T01:49:07.102473282Z",
  "published": "2026-06-24T19:40:35.022Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46349.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/mastodon/mastodon/security/advisories/GHSA-chgx-jx3p-rf73"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46349"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Mastodon: LD-Signature Bypass via JSON-LD Named-Graph Restructuring"
}