Following the spread of the dreaded Petya ransomware that did the rounds yesterday and locked people out of their files on some 300,000 computers across the globe, victims are finding themselves in another pickle as they can’t contact the hacker who holds the key to their data.

The problem: an angry email service provider.

As is the case with such attacks, the hacker’s ransomware included a message that urged victims to pay $300 in Bitcoin in order to have their files decrypted and restored.

But unlike similar attacks where people have transferred funds to unique Bitcoin wallets for each case, all Peyta victims were instructed to pay up and then send details like their Bitcoin wallet ID and the personal installation key generated by the malware on their computers to a single email address.

But now, German email service Posteo has blocked that address, so the hacker can’t access their inbox and people can’t send messages to it either.

That’s bad news for the 20-or-so victims who, according to Motherboard, have paid about $5,000 in total to the hacker.

It’s worth noting that we can’t be sure if the hacker is capable or even actually intended to decrpyt the files for those who paid the ransom.

Posteo told Motherboard, “Please make no speculations about how high the chances are to decrypt files locked by ransomware if you pay a criminal.”

As always, the best defense against ransomware is backing up your data often, so you never have to give in to hackers’ demands. It might sound easier said than done, but with such attacks on the rise, it’s about time everyone got with the program.

Info on the PetrWrap/Petya ransomware: Email account in question already blocked since midday on Posteo

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