CVE-2026-63566

{
  "etk_id": "ETK-2026-320",
  "cve_id": "CVE-2026-63566",
  "display_id": "CVE-2026-63566",
  "ghsa_id": "GHSA-496x-2f25-59fj",
  "euvd_id": "EUVD-2026-91217",
  "status": "published",
  "anchor_state": "anchored",
  "title": "Excessive DTLS handshake memory allocation in BouncyCastle.Cryptography",
  "summary": "BouncyCastle.Cryptography versions before 2.7.0 can allocate excessive memory while reassembling DTLS handshake messages. An unauthenticated remote DTLS peer may exhaust process memory and cause a denial of service when it can initiate a DTLS handshake; DTLS clients and servers are affected, but TLS is not.",
  "mitigation": "Upgrade BouncyCastle.Cryptography to version 2.7.0. Until upgraded, restrict DTLS handshake access to trusted peers where feasible.",
  "vendor": "Legion of the Bouncy Castle Inc.",
  "product": "bc-csharp",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 0, < 2.7.0"
      ],
      "ecosystem": null,
      "fixed_versions": [
        "2.7.0"
      ],
      "package_name": "BouncyCastle.Cryptography",
      "purl": null
    }
  ],
  "cwes": [
    789
  ],
  "cvss_score": 8.7,
  "cvss_src": "cna_vendor",
  "cvss_vector": "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",
  "epss_score": 0.0037,
  "epss_percentile": 0.2963,
  "epss_asof": "2026-10-20",
  "automation": "deterministic",
  "check": false,
  "check_confidence_basis": null,
  "exploit": false,
  "pipeline_minutes": 90.24537958333333,
  "t0_at": "2026-10-02T06:57:21.718000+00:00",
  "signals": {
    "trigger_signal": {
      "at": "2026-10-02T06:57:21.718000+00:00",
      "days": 0,
      "is_lower_bound": false,
      "measured_at": "2026-10-02T06:57:21.718000+00:00",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-63566"
    }
  }
}