All the features mentioned previously are common to all PETYA versions. The images shown previously belong to RED-PETYA, which was the first version of PETYA.

RED-Petya used Salsa20, a symmetric key algorithm, to encrypt the MFT and make disks inaccessible. However, the implementation of the algorithm was not done correctly, which resulted in an unintended bug. Researchers were able to write decryptors to disinfect Petya-infected machines. The bug was fixed in later versions of Petya.