A new ransomware is spreading around the world. It’s already hit a number of European countries, may or may not have hit the US, and has even affected Interfax, a Russian news agency. Named Bad Rabbit, it’s a newer version of NotPetya and is suspected to have come from North Korea.
As ransomware goes, Bad Rabbit is a pretty big improvement over its predecessor. For one thing, the decryption actually works, which means if you pay the ransom (0.05₿, which as of this writing is $298.50), you’ll actually get your files back. The encryption itself is more sophisticated. It encrypts files like any other ransomware, but then it replaces the Master Boot Record, rendering the computer completely useless. It also means you need two decryption keys: one for the MBR and one for the files.
Bad Rabbit makes use of a program called Mimikatz to get password information from the system. Mimikatz looks in the computer’s memory for passwords, PINS, and other secret information it can use. It also uses common usernames like admin or administrator or root along with common passwords to guess needed credentials. (So let that be YET ANOTHER reminder to not use easy or common passwords.)
From what experts can tell, the Bad Rabbit outbreak started when malicious code was inserted into Russian media websites. When visiting one of these sites, a user is prompted to install an Adobe Flash update. Of course it’s not really a Flash update, and clicking to install the update actually installs the ransomware.