CVE-2026-102599

{
  "etk_id": "ETK-2026-48",
  "cve_id": "CVE-2026-102599",
  "display_id": "CVE-2026-102599",
  "ghsa_id": "GHSA-2gc4-cqfq-p2gv",
  "euvd_id": "EUVD-2026-100462",
  "status": "published",
  "anchor_state": "anchored",
  "title": "Engine.IO transport-upgrade protocol validation flaw",
  "summary": "The npm engine.io package is affected in versions 6.6.0 through 6.6.9 when servers permit transport upgrades. A remote client that can create a session may cause the Node.js process to exit by triggering inconsistent protocol handling during an upgrade.",
  "mitigation": "Upgrade engine.io to version 6.6.10 or later; update dependent Socket.IO packages to a release that includes it. Until then, disable transport upgrades or restrict the deployment to a single transport where compatible.",
  "vendor": "npm",
  "product": "npm:engine.io",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 6.6.0, < 6.6.10"
      ],
      "ecosystem": "npm",
      "fixed_versions": [
        "6.6.10"
      ],
      "package_name": "engine.io",
      "purl": "pkg:npm/engine.io"
    }
  ],
  "cwes": null,
  "cvss_score": 7.5,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "epss_score": 0.0058,
  "epss_percentile": 0.469,
  "epss_asof": "2026-10-20",
  "automation": "contextual",
  "check": true,
  "check_confidence_basis": "assessed",
  "exploit": false,
  "pipeline_minutes": 10.2925457,
  "t0_at": "2026-10-13T19:05:10.870000+00:00",
  "signals": {
    "check": {
      "at": "2026-10-13T19:35:18.286125+00:00",
      "days": 0.020919168113425927,
      "is_lower_bound": false,
      "measured_at": "2026-10-13T19:05:10.870000+00:00",
      "url": null
    },
    "trigger_signal": {
      "at": "2026-09-29T23:44:33+00:00",
      "days": -13.80599386574074,
      "is_lower_bound": false,
      "measured_at": "2026-10-13T19:05:10.870000+00:00",
      "url": "https://github.com/advisories/GHSA-2gc4-cqfq-p2gv"
    }
  }
}