The promotion of the concept of "magical immunity" to computer viral attacks surfaces on a regular basis. This concept, while desirable, is misleading and dangerous since it tends to mask a real threat. Opponents of the possibility of viral attacks in Unix state that hardware instructions and operating system concepts, such as supervisor mode or permission settings and security ratings like C2 or B1, provide protection. These ideas have been proven wrong in real life. The use of supervisor mode, the additional levels of protection provided by C2 and the mandatory access control provided by security level B1, are not necessary for viral activity and are therefore moot as a method of protection. This fact is supported by the existence of viruses that infect Unix systems as both scripts and binary.