{"id":"CVE-2020-15133","details":"In faye-websocket before version 0.11.0, there is a lack of certification validation in TLS handshakes. The `Faye::WebSocket::Client` class uses the `EM::Connection#start_tls` method in EventMachine to implement the TLS handshake whenever a `wss:` URL is used for the connection. This method does not implement certificate verification by default, meaning that it does not check that the server presents a valid and trusted TLS certificate for the expected hostname. That means that any `wss:` connection made using this library is vulnerable to a man-in-the-middle attack, since it does not confirm the identity of the server it is connected to. For further background information on this issue, please see the referenced GitHub Advisory. Upgrading `faye-websocket` to v0.11.0 is recommended.","aliases":["GHSA-2v5c-755p-p4gv"],"modified":"2026-07-09T00:22:36.930773Z","published":"2020-07-31T18:15:14.473Z","references":[{"type":"EVIDENCE","url":"https://blog.jcoglan.com/2020/07/31/missing-tls-verification-in-faye/"},{"type":"EVIDENCE","url":"https://github.com/faye/faye-websocket-ruby/security/advisories/GHSA-2v5c-755p-p4gv"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/faye/faye-websocket-node","events":[{"introduced":"0"},{"fixed":"dc392490a8e84b9735aab0e306a2b477a6e84ce5"}],"database_specific":{"cpe":"cpe:2.3:a:faye-websocket_project:faye-websocket:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"0.11.0"}],"source":"CPE_RANGE"}}],"versions":["0.10.0","0.9.4","0.9.3","0.9.2","0.9.1","0.9.0","0.8.1","0.8.0","0.7.3","0.7.2","0.7.1","0.7.0","0.6.1","0.6.0","0.5.0","0.4.4","0.4.3","0.4.2","0.4.1","0.4.0","0.3.1","0.3.0","0.2.0","0.1.2","0.1.1","0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-15133.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N"}]}