I am currently working on a problem where I have two encrypted messages, their corresponding signatures, and the public key. Furthermore, the value of $r$ is the same in the two signatures. I am trying to recover the plaintext messages and stumbled upon the Wikipedia : Elliptic Curve DSA page that explains that one can recover the private key given two cleartext messages, and their corresponding signatures where r is the same in both signatures. The problem is I don't have the cleartext messages, so I am wondering if it is possible to derive the private key and subsequently decrypt the messages from the givens that I currently have.
fail0verflow announced recovery of the ECDSA **private key**
$\endgroup$ – kelalaka Dec 23 '18 at 18:26