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I have the following question about TLS security:
Assume TLS-PSK protected HTTP with AES256-CBC cipher.
When a TLS connection is established, client sends some encrypted data, where the
plaintext is well known to an attacker.
For example, it can be a HTTP request, like:
GET /some_resource HTTP/1.1 ...
Can an attacker use intercepted ciphertext and known plaintext it to reveal the secret key?
Does TLS have any features to protect from that?