A computer virus is defined as a program that potentially causes damage to hardware, software or any data within a network. For businesses, it can drastically damage business operations, cooperation and client-vendor relationships.
Computer viruses got their name as they share certain characteristics of biological viruses. Computer viruses spread from one computer to another like a biological viruses are passed between individuals without having the ability to reproduce by themselves. While biological viruses integrate themselves into the DNA of infected cells and use the cell’s existing replication machinery to reproduce, a computer virus program piggybacks itself to another program (file, document, boot sectors of a disk) and gets into the system memory when the file is executed.
Biologically viruses spread after being released from a cell that bursts or travel through the cell membrane, while computer viruses replication and spreading means that viruses, once in system memory, may search for further files that they can infect or they may work from the background infecting other files that are used by the originally infected file.
A huge danger today, since email is uninterruptedly used for business as well as private operations, are email viruses that spread within different computers as attachment of messages. They usually replicate themselves by automatically sending themselves to users found in the original infected user’s email address book. Some email viruses don’t even require completely opening the attachment but launch when viewing the infected message preview.
Routes viruses use to infect computers include:
- Email: viruses attached to emails reach thousands of user’s when opening emails or email attachments
- Removable media: in old days via floppy disk, viruses spread today through devices such as USB and other devices
- Network Shares: malware spreads through the network when security procedures are poorly implemented
- Network scanning: after scanning networks for vulnerable computers, malware is injected into the vulnerable system
- Peer to peer (P2P) networks: installing a “new” component can make file system accessible to other virus spreading computers across networks
- Mobile networks: viruses attached to messages and apps, reach thousands of mobile users when opening messages and using apps
Ever more businesses are using cloud services (SaaS and PaaS) providing the “perfect” client oriented applications. However, that makes them also more susceptible to modern virus attacks. Thus, innovative anti-virus software needs to be advanced to keep track of these developments.