Black Basta is a new emerging ransomware that encrypts data stored on clients’ hard drives. It has been active since April 2022 and employs a double-extortion attack technique. In July 2022, the Black Basta ransomware group has added a new capability that encrypts VMware ESXi virtual machines (VMs) on Linux servers
A new strain of the Black Basta ransomware that supports encryption of VMWare ESXi servers. They have been reporting on similar encryptors issued by a number of different groups, including LockBit, HelloKitty, BlackMatter, REvil, AvosLocker, RansomEXX, and Hive, among others.
Black Basta’s ransomware binary, like other Linux encryptors, will search for the /vmfs/volumes where virtual machines are kept on the compromised ESXi servers (if no such folders are found, the ransomware exits).
To encrypt the data, the ransomware uses the ChaCha20 algorithm. It also uses multithreading to make use of many processors and accelerate the encryption operation. The ransomware appends the .basta extension to encrypted filenames and creates readme.txt ransom notes in each folder.