Send IV encrypted or not? [closed]

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I'm using CBC mode. I'm thinking of sending the IV encrypted in ECB mode(since it is only a block), instead of sending the "plain" IV. Will i gain some security?

Answer 1

You do not need to encrypt the IV in CBC mode. There is no security advantage. See an earlier answer of mine on the 'proof' of why. Sending IV along with cipher text, safe?.

The short answer is, when you look at CBC mode, the previous ciphertext block effectively becomes the IV for the next block. We transmit the ciphertext blocks in the clear (if that makes sense?), and so if there were a risk with the first block, there would be a risk for every block.