QTINeon has unauthenticated relay-to-host amplification via unbounded RECONNECT_REQUEST forwarding

{
  "id": "8698ea74bbf67edcc30ab18c82902b1a5d7bda63cc67b0ebebcae28f33321ccf",
  "url": "https://osv.dev/vulnerability/CVE-2026-54609",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "QTINeon has unauthenticated relay-to-host amplification via unbounded RECONNECT_REQUEST forwarding",
    "summary": "QTI Neon is a minimal, game-agnostic, relay-based UDP multiplayer protocol library. In version 1.0.0, the relay's handleReconnectRequest forwards RECONNECT_REQUEST packets to the host without bounding them, so an unauthenticated client can drive relay-to-host amplification and cause a denial of service on the host. No fixed version is available as of this review.",
    "evidence": "osv:CVE-2026-54609",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-54609",
      "aliases": [
        "CVE-2026-54609",
        "GHSA-85rg-p3fr-xc2f",
        "PYSEC-2026-3615"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/quiet-terminal-interactive/qtineon",
              "type": "GIT",
              "events": [
                {
                  "introduced": "64c3cb67e8e758b870413ec797ffee256e5c8c45"
                },
                {
                  "last_affected": "64c3cb67e8e758b870413ec797ffee256e5c8c45"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "1.0.0"
                      },
                      {
                        "last_affected": "1.0.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandaloneSingleVersion"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.0.0",
            "godot-v1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54609.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:40.260612502Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54609.json",
        "https://github.com/Quiet-Terminal-Interactive/QTINeon/security/advisories/GHSA-85rg-p3fr-xc2f",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-54609"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-400",
          "CWE-406",
          "CWE-770"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54609.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-54609",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 508115,
  "published_at": "2026-07-28T16:36:37.938+00:00"
}