A Windows Security Scanner that states it encrypted your files is being distributed by spam. The program instead corrupts binary data in a victim’s files. It is not known if the attacker is purposely trying to corrupt data, but based on some of the strings stuffed into the program, it could be intentional. The malware is meant to only work with text files, binary files such as images, docs, spreadsheets, etc will be corrupted when it writes the data back as text. The binary data is being corrupted because the program is using the File.ReadAllLines method to read the contents of a file into an array.
Source: https://www.bleepingcomputer.com/news/security/lost-files-data-wiper-poses-as-a-windows-security-scanner/