⟩ Suppose you manage to capture email packets from a sender that are encrypted through Pretty Good Privacy (PGP). What are the most viable options to circumvent this?
First, one should be considering whether to even attempt circumventing the encryption directly. Decryption is nearly impossible here unless you already happen to have the private key. Without this, your computer will be spending multiple lifetimes trying to decrypt a 2048-bit key. It’s likely far easier to simply compromise an end node (i.e. the sender or receiver). This could involve phishing, exploiting the sending host to try and uncover the private key, or compromising the receiver to be able to view the emails as plain text.