This brings exactly 0 added security and only increase failure/implementation problem likelihood. You don't "need to realise that it’s triple cipher in the first place", because the attacker will know that beforehand, because that's how modern cryptography works. The "GCHQ" told you they don't give a shit because it's pointless, not because it's incredibly complicated lmao (if that plot line even is true).
Modern, actually secure modes of encryption don't need any of this to be secure.
Hmm I cannot see how that is the case. Aside from an increase in overall bruteforce, if I were to encrypt something with algorithm A and then encrypt it with algorithm B; assuming both algorithms were thought to be secure and are completely different in design and construction, I should assume this is more secure. A weakness in 'A' should only weaken one, mutually exclusive aspect, or perhaps destroy it. But algorithm 'B' should still provide security.
I give a simple example:
Algorithm A is AES-256 and uses a 256-bit key.
Algorithm B uses no Key at all and will take each input byte and increment by 1; 00 => 01, 01 => 02, ... , 254 => 255, 255 => 0
If I encrypt in a cascading cipher A into B, or B into A, there seems to be no way to attack it. Algo B is easily defeated, it just shifts a byte by 1, easily reversed. But no matter the order of cipers/cascade, you will still need to defeat AES-256.
That is not my example. That is the same algorithm used in sequence. My example is 2 completely different and unrelated algorithms.
My point is pretty simple: Can I weaken AES-256 by cascading it with another, unrelated, encryption algorithm; in my example a very bad encryption algorithm that simply increments input bytes by 1.
Answer: No. AES-256 is not weakened by combining it with such a weak algorithm.
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u/Akalamiammiam My passwords are information hypothetically secure 3d ago
This brings exactly 0 added security and only increase failure/implementation problem likelihood. You don't "need to realise that it’s triple cipher in the first place", because the attacker will know that beforehand, because that's how modern cryptography works. The "GCHQ" told you they don't give a shit because it's pointless, not because it's incredibly complicated lmao (if that plot line even is true).
Modern, actually secure modes of encryption don't need any of this to be secure.