Vulnerability Description
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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Faye-Websocket Project | Faye-Websocket | < 0.11.0 |
Related Weaknesses (CWE)
References
- https://blog.jcoglan.com/2020/07/31/missing-tls-verification-in-faye/ExploitThird Party Advisory
- https://github.com/faye/faye-websocket-ruby/security/advisories/GHSA-2v5c-755p-pExploitThird Party Advisory
- https://blog.jcoglan.com/2020/07/31/missing-tls-verification-in-faye/ExploitThird Party Advisory
- https://github.com/faye/faye-websocket-ruby/security/advisories/GHSA-2v5c-755p-pExploitThird Party Advisory
FAQ
What is CVE-2020-15133?
CVE-2020-15133 is a vulnerability with a CVSS score of 8.0 (HIGH). 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 t...
How severe is CVE-2020-15133?
CVE-2020-15133 has been rated HIGH with a CVSS base score of 8.0/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2020-15133?
Check the references section above for vendor advisories and patch information. Affected products include: Faye-Websocket Project Faye-Websocket.