In the same way earthworms burrow and tunnel their way through the ground, a cyberattack worm can make its way throughout an entire network. The goal is to infect as many other systems as possible after the first one is infected and computer worms do their work quickly. A worm that’s been programmed to infect an Instant Messaging network can attempt to infect more than 3 million systems in five minutes if each person in the network has only 20 IM contacts.

Some Early Famous Worm Attacks

The first computer worm was set loose in 1988 by Robert Tappan Morris, a computer science grad student at Cornell University. His cyberattack disrupted an estimated one-tenth of the computers connected to the Internet at that time. Morris was the first individual tried and convicted under the Computer Fraud and Abuse Act.

Twelve years after Morris unleashed his malware, the ILOVEYOU worm relied upon an email attachment to activate. When the attachment was opened, the script was activated and sent copies of the virus to all the Windows Address Book emails listed on the infected computer. Tens of millions of Windows-based personal computers were infected when recipients opened the LOVE-LETTER-FOR-YOU.txt.vbs attachment.  More than 50 million infected computers were reported over a ten-day period.

The Blaster worm spread across computers running the Windows 2000 and Windows XP operating system in August 2003. Once the worm made its way into a company or university system, it spread quickly throughout those networks. It took no more than two days for millions of Windows systems to become infected and many networks were shut down.

The New Breed of Cyber-Worms

Computer worms no longer limit themselves to email delivery systems. Social media sites, such as Facebook, have become additional transmission methods. Social media malware attacks can spread by sending messages to other potential victims from the infected user’s account. These impersonator messages will appear to have come from the infected user’s computer.

The portion of a worm that does more than just spread itself is called its payload. One of the more malicious functions of a payload is to install what’s called a backdoor. This allows a remote operator to access a computer or system and read, download or delete files without requiring a password. A backdoor is considered one of the most dangerous forms of malware because it allows a remote user to perform any possible action on the infected computer.

Safety Practices

One of the basic preventive measures you can take against malware is to not open email attachments that either look suspicious or come from someone you don’t know. Don’t click on any links in pop-up windows or emails, even if they attempt to make it sound urgent. Protecting your computer or system with multi-layered antivirus and firewall software is one of the best overall approaches to security you can take. Don’t make the mistake of sacrificing your system’s security by using a free software solution; choose carefully and be sure you’re getting all the protection and features you need.