CVE-2021-4236: Github.com/ecnepsnai/web Websocket Requests Did Not Call Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-5gjg-jgh4-gppm",
  "modified" : "2026-01-23T22:35:54Z",
  "published" : "2021-06-23T17:26:30Z",
  "aliases" : [ "CVE-2021-4236" ],
  "summary" : "Websocket requests did not call AuthenticateMethod",
  "details" : "### Impact\n\nDepending on implementation, a denial-of-service or privilege escalation vulnerability may occur in software that uses the `github.com/ecnepsnai/web` package with Web Sockets that have an AuthenticateMethod.\n\nThe `AuthenticateMethod` is not called, and `UserData` will be nil in request methods. Attempts to read the `UserData` may result in a panic.\n\nThis issue only affects web sockets where an `AuthenticateMethod` is supplied to the handle options. Users who do not use web sockets, or users who do not require authentication are not at risk.\n\n#### Example\n\nIn the example below, one would expect that the `AuthenticateMethod` function would be called for each request to `/example`\n\n```go\nhandleOptions := web.HandleOptions{\n\tAuthenticateMethod: func(request *http.Request) interface{} {\n\t\t// Assume there is logic here to check for an active sessions, look at cookies or headers, etc...\n\t\tvar session Session{} // Example\n\n\t\treturn session\n\t},\n}\n\nserver.Socket(\"/example\", handle, handleOptions)\n```\n\nHowever, the method is not called, and therefor the `UserData` parameter of the request object in the handle will be nil, when it would have been expected to be the `session` object we returned.\n\n### Patches\n\nRelease v1.5.2 fixes this vulnerability. The authenticate method is now called for websocket requests.\n\nAll users of the web package should update to v1.5.2 or later.\n\n### Workarounds\n\nYou may work around this issue by making the authenticate method a named function, then calling that function at the start of the handle method for the websocket. Reject connections when the return value of the method is nil.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/ecnepsnai/web"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.4.0"
      }, {
        "fixed" : "1.5.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/ecnepsnai/web/security/advisories/GHSA-5gjg-jgh4-gppm"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-4236"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ecnepsnai/web/commit/5a78f8d5c41ce60dcf9f61aaf47a7a8dc3e0002f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/ecnepsnai/web"
  }, {
    "type" : "WEB",
    "url" : "https://pkg.go.dev/vuln/GO-2021-0107"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-304", "CWE-400", "CWE-476" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-05-21T17:41:20Z",
    "nvd_published_at" : null
  }
}