# Tag Info

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Short version: the signature is correct, it is a real signature and therefore it is possible to verify it with one's favourite software. The scam is not based on a cryptographic attak but on what is signed. Craig Wright has recovered an old (and real) Satoshi's signature and tried to provide it as a new signature to validate his identity. It's, as someone ...

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I don't have enough space to expand on yyyyyyy's answer in a comment so I am making this an answer in and of itself. TruthSerum is correct, but it seems like an explanation is wanted, so here goes. Imagine you have a regular (all the sides have the same length, all the angles are the same) n-gon. That sounds complex, but trust me it isn't. A 4-gon is ...

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So my question is, if they are the ones who encrypt this, then why can't they also decrypt it? Because it’s not them encrypting your message, it’s the App on your device… which is why it’s called End-To-End encryption. According to the security whitepaper (PDF), WhatsApp uses the Noise Protocol Framework which is based on the Signal protocol (formerly ...

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Scheme is not IND-CPA for any message longer than one block. I'll include a image of CBC mode below for reference (Source: Wikipedia). Suppose instead of block cipher encryption we have plaintext xor-ed with the key as you propose. You'll note that for message block 1, $M_1$, the ciphertext block $C_1 = M_1 \oplus IV \oplus Key$. Similarly \$C_2 = M_2 ...

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If you ask about the protocol itself, as a theoretical construct, then it is safe. In theory it indeed provides all the feature that it promises. And now for the "but..." part. When you use a protocol to communicate, you are actually using one implementation of the protocol. The implementation tries to do exactly what the protocol says. However you can ...

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I would not consider your case to be a cascading encryption. The reason why is the fact you need multiple interventions before getting access to your file. Here is what I would consider a cascading encryption (let's go crazy) : $$E(k_1,k_2,k_3,m) = \text{KEYAK}(k_1,\text{NORX}(k_2,\text{AES}(k_3,m)))$$ which you would decipher with : ...

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Functional encryption might fit your description; as far as I know it's still far from practical though.

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I haven't looked at watsapp specifically, this is a general answer on the practicalities of this. It's possible to have end to end encryption where the private key never leaves the client. If the provider doesn't have the private key then they can't decrypt the traffic. There are two problems though. Can alice and bob trust the client to do what it says ...

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Since the client is not open source, you cannot verify their statement. That is, it could very well be encrypted but in a way that would allow either WhatsApp or another third party to break the security. To verify that it does encrypt data, you could use tools like WireShark to see whether text messages are sent in plain or encoded/encrypted. Bottom line: ...

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In a sense, I don't think it matters. It's probably realistic for average users who aren't under direct investigation by a government for high-level drug-, terrorism-, or leak-related offenses. If you have reason to suspect you may fall under one of those categories, it's in your best interest not to trust that WhatsApp isn't capable or can't be compelled ...

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