Security advisory

{
  "id": "92b460ed36d94ea27f6ff50637fe62549c6a3b3547d5c75b681ab73a09fb9594",
  "url": "https://osv.dev/vulnerability/CVE-2025-49090",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2025-49090",
    "summary": "The Matrix specification before 1.16 (i.e., with a room version before 12 and State Resolution before 2.1) has deficient state resolution.",
    "evidence": "osv:CVE-2025-49090",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2025-49090",
      "aliases": [
        "CVE-2025-49090"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/matrix-org/matrix-spec",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "81a864545f7d948a881f5227700e5312c64f506e"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.16"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "fixed": "81a864545f7d948a881f5227700e5312c64f506e"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v1.16"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.16"
                      }
                    ],
                    "source": "DESCRIPTION"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.15",
            "v1.14",
            "v1.13",
            "v1.12",
            "v1.11",
            "v1.10",
            "v1.9",
            "v1.8",
            "v1.7",
            "v1.6",
            "v1.5",
            "v1.2",
            "push_gateway/r0.1.0",
            "client-server/0.3.0",
            "client-server/r0.1.0",
            "r0.0.1",
            "r0.0.0",
            "0.2.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-49090.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:37.399269178Z",
      "provider": "osv",
      "references": [
        "https://github.com/matrix-org/matrix-spec/releases/tag/v1.16",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/49xxx/CVE-2025-49090.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-49090",
        "https://github.com/Nheko-Reborn/nheko/issues/1931",
        "https://matrix.org/blog/2025/08/project-hydra-improving-state-res/",
        "https://matrix.org/blog/2025/08/security-release/"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-642"
        ],
        "cna_assigner": "mitre",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/49xxx/CVE-2025-49090.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-49090",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 504725,
  "published_at": "2025-10-02T00:00:00+00:00"
}