A system and method for encrypting an electronic file in a mobile electronic device reads bytes of the electronic file from a cache of a memory system and divides the bytes into a plurality of byte lines. The system and method further assigns a numerical cipher to each byte line and searches a position of each numerical cipher in a corresponding byte line. Furthermore, the system and method encrypt each byte line by inserting one or more random bytes into each byte line, and generates an encrypted electronic file by combining all the encrypted byte lines.