{
  "affected": [
    {
      "database_specific": {
        "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/07/GHSA-2x63-gw47-w4mm/GHSA-2x63-gw47-w4mm.json"
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "websocket-driver",
        "purl": "pkg:gem/websocket-driver"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.8.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.1.0",
        "0.2.0",
        "0.2.1",
        "0.2.2",
        "0.2.3",
        "0.3.0",
        "0.3.1",
        "0.3.2",
        "0.3.3",
        "0.3.4",
        "0.3.5",
        "0.4.0",
        "0.5.0",
        "0.5.1",
        "0.5.2",
        "0.5.3",
        "0.5.4",
        "0.6.0",
        "0.6.1",
        "0.6.2",
        "0.6.3",
        "0.6.4",
        "0.6.5",
        "0.7.0",
        "0.7.1",
        "0.7.2",
        "0.7.3",
        "0.7.4",
        "0.7.5",
        "0.7.6",
        "0.7.7",
        "0.8.0",
        "0.8.1"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-61666"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-248"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-21T18:34:42Z",
    "nvd_published_at": "2026-08-17T17:16:39Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nIf this library is used to implement a WebSocket server on top of a TCP server, by using the `WebSocket::Driver.server()` method, then a client can cause the server to crash by sending a `Host` header that is not a valid `host[:port]` string. When this happens, a `URI::InvalidURIError` exception is raised which is not caught, and this can cause the server process to crash if the application does not catch the error from the `parse()` method itself.\n\n### Patches\n\nThe issue has been patched in version 0.8.2 by making the request parser catch `URI::InvalidURIError` and enter an error state if the `Host` header is malformed. This means the request is considered invalid and should not establish a WebSocket connection.\n\n### Workarounds\n\nNo known workarounds exist.\n\n### Acknowledgements\n\nThis issue was discovered and reported by Pranjali Thakur, DepthFirst Security Research Team.",
  "id": "GHSA-2x63-gw47-w4mm",
  "modified": "2026-11-02T21:15:04.252525532Z",
  "published": "2026-07-21T18:34:42Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/faye/websocket-driver-ruby/security/advisories/GHSA-2x63-gw47-w4mm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-61666"
    },
    {
      "type": "WEB",
      "url": "https://github.com/faye/websocket-driver-ruby/commit/7d6fd87759a2fdc83590d3b49ffa661dc53fa128"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/faye/websocket-driver-ruby"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/a58f1d0a3343e85cef597970f2c5458dcfbaf909/gems/websocket-driver/CVE-2026-61666.yml"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H",
      "type": "CVSS_V4"
    }
  ],
  "summary": "websocket-driver-ruby: Denial of service via malformed Host header"
}