As the anti-viruses run in a trusted kernel level any loophole in the anti-virus program can enable attackers to take full control over the computer system and steal data or do serious damages. Hence the anti-virus engines must be developed with proper security in mind... The ant-virus should be able to any type of specially created executable files, compression packages or documents that are intentionally created to exploit the anti-virus weakness. Viruses are present in almost every system even though there are anti-viruses installed. This is because every anti-virus, however good it may be, leads to some extent of false positives and false negatives. Our faith on the anti-virus system often makes us more careless about hygienic habits which increases the possibility of infection. It is necessary for an anti-virus to detect and destroy the malware before its own files are detected and destroyed by the malware. (read more)