This ransomware uses XOR cipher to encrypt the files. It will only affect non-system files under User desktop's directory. This is limited to User's directory but you can specify another relative instead of Desktop's one or None by changing RELATIVE_FOLDER's value in main.c.
Once you run the program it will check if the first file is encrypted or not. If it´s not encrypted it will encrypt all the not encrypted others and vice versa.
In case you want to have it in a pen to auto-execute but at the same time avoiding running it in your own computer when inserting the pen you could add the following key and value to your system's variable.
Key: H43_xor_encryption
Value: H43
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