Iowa State University

ITInformation Technology

Malware, its many shapes and sizes

This blog entry expired November 26, 2016. It may contain out-of-date information.

Malware, a term describing malicious software, infects and harms devices and systems to gain access to personal information. Malware can be destructive if exposed to a device or system. To protect yourself against malware it is important to know the different forms that malware can take.  


Computer viruses, a form of malware, can only operate with human interaction, so they cannot infect or spread to computers without a human action. Downloading an attachment or clicking a link infects the device or system and spreads the virus. Viruses take many forms and easily spread from one place to the next. Installing antivirus software on all of your devices reduces the risk of getting a virus.  


When malware no longer requires human interaction to infect devices it is considered a worm. Worms are programs that spread through as many devices as possible. They seek vulnerabilities in software and once they find them, they replicate and move through systems and networks to find more. Regularly updating software helps prevent vulnerabilities and the risk of worms.  

Email Attachments

Malware also travels through email attachments, with the hope of being downloaded and allowed to embed some sort of malicious software, such as a virus, onto a device. Always be cautious of clicking on links or downloading files from unknown or untrusted sources.  


Scareware is a type of malware that deceives people to infect a device. It appears in the form of a message alerting users that a virus has been detected on their device. By clicking a link in the message, it can be removed. When actually there was no virus detected and clicking the link caused a virus to appear.

Malicious Adware

Malware appears in the form of malicious advertisements or pop-up windows that harm devices. It is never a good idea to click on a suspicious advertisement or pop-up windows. If something like that does appear, the best thing to do is to close out of the browser all together. 

All of these types of malware have the same purpose, to compromise your device or software and steal your information, so be aware and stay alert.