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35

Yes, HSTS is still needed, including HSTS preload. The way a browser connects to HTTP/2 is through a URL that looks exactly the same as the URL for HTTP/1, so it doesn't know that it must be HTTP/2 just from looking at the URL. It will try plain cleartext HTTP if it is given a http:// URL. In order for the browser to not try plain HTTP (and not be subject ...


4

The requests to those APIs will fail. This is because browsers will try to do a handshake with the API server, and only accept servers who support TLS 1.2 or TLS 1.3. If those servers don't support either of those, the client will reject the connection. As a result, you have several options on how to proceed now, each with varying pro's and con's. Request ...


3

This looks like a wrong interpretation of the data. What most likely happened is that some TCP segments got out of order or lost, confusing the TLS dissector in Wireshark. This seems to be supported by your observation of retransmitted packets. Some applications also do not align the start of a TLS records with the begin of a TCP segment when a lot of data ...


3

The Secure Remote Password (SRP) protocol can be used to send credentials over an unencrypted network. You could also require SSL/TLS client authentication which will prevent the proxy from being able to establish a connection to the web server.


2

Short version: No. While POODLE can be used with MitM to decrypt some HTTPS traffic in specific scenarios, it requires special effort / software (not just Wireshark) and is not going to be usable against up-to-date HTTPS (or any other kind of TLS traffic). POODLE (Padding Oracle On Downgraded Legacy Encryption) is an attack that can leak data from certain ...


1

The POODLE (Padding Oracle On Downgraded Legacy Encryption) attack affects any connection which uses SSL 3.0 as its encryption standard, along with CBC (Cipher Block Chaining). SSL 3.0 is an old standard and is replaced by TLS now, the problem stems from the fact that most SSL/TLS implementations remain backward compatible, to help with legacy systems. A ...


1

You are correct on both your first 2 points. As a protection against attacks such as SSLstrip, the HSTS header prevents an attacker from downgrading a connection from HTTPS to HTTP, as long as the attributes of the header are properly configured. Yes, so the HSTS header tells the browser to only access the web server over a secure connection, thereby ...


1

If attacker gets access to a private key material of the server certificate, your security is compromised. What you can do is to add security to key storage and store the key in HSM (Hardware Security Module).


1

It is perfectly fine to use a cryptographic hash ("fingerprint") of the certificate for comparison instead of the certificate itself. And this is actually often done when implementing certificate pinning. A man in the middle would not be able to generate a certificate and matching private key where the certificate has exactly the same fingerprint as your ...


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