CVE-2020-15133

Public Exploit
Missing TLS certificate verification in Faye Websocket

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.

Category

8.0
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.14%
Third-Party Advisory jcoglan.com Third-Party Advisory github.com
Affected: faye faye-websocket
Published at:
Updated at:

References

Link Tags
https://blog.jcoglan.com/2020/07/31/missing-tls-verification-in-faye/ third party advisory exploit
https://github.com/faye/faye-websocket-ruby/security/advisories/GHSA-2v5c-755p-p4gv third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2020-15133?
CVE-2020-15133 has been scored as a high severity vulnerability.
How to fix CVE-2020-15133?
To fix CVE-2020-15133, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-15133 being actively exploited in the wild?
It is possible that CVE-2020-15133 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-15133?
CVE-2020-15133 affects faye faye-websocket.
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