Companies that paid the ransom to retrieve their data from the Petya ransomware attack have no way of receiving the encryption key. Although Symantec has verified the Ukrainian accounting service, MeDoc, as “patient zero” for the attack, the cybersecurity company hasn’t discovered who is behind the attack. The email account that the attack stemmed from has been shut down, so that companies that pay the ransom of $300 won’t receive the encryption key needed to return their data. […]