DiceCTF baby-rsa writeup

This was an RSA challenge, but DiceGang are always creative and they mixed it up quite a bit! The general gist is that we are given an RSA encrypted ciphertext whose e value is not coprime with its phi [(p-1)(q-1)] value. In RSA, non-coprime phi and e don’t actually make the encryption non-secure, they make it non-invertible which means we can’t uniquely decrypt the ciphertext.

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