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Some corporate firewalls MITM all https connections. Websocket does not look normal once you've terminated TLS.
by toast0 2y ago
Some corporate firewalls MITM all https connections. Websocket does not look normal once you've terminated TLS.
- amelius 2y agoCan websites detect this?
- toast0 2y agoAFAIK, only by symptoms. If https fetches work and websockets don't, that's a sign. HSTS and assorted reporting can help a bit in aggregate, but not if the corporate MITM CA has been inserted into the browser's trusted CA list. I don't think there's an API to get certificate details from the browser side to compare. A proxy may have a different TLS handshake than a real browser would, depending on how good the MITM is, but the better they are, the more likely it is that websockets work.