Overview of viruses and malware and how to protect your computer

To protect your computer and your data, you should use a combination of anti-virus software, anti-spyware software, critical updates, safe habits, and common sense.

Malware and Viruses

Malware is a catch-all term that can be used to describe any invasive or malicious software that threatens your computer's security or data. While there are technical differences between them, viruses, spyware, worms, trojans, root kits, and other unwanted software can all be classified as malware.

What are the effects of malware?

There are lots of nasty things malware can do to your computer. Corrupt files, sluggish computer performance, browser hijacks, and pop-up advertisements are just a few things you can expect from malware.

When computer becomes infected with malware, regardless of whether it is a virus or some other form of malicious software, you will usually notices poor performance, corrupt data, or performance problems. You may notice that certain websites fail to load, especially websites that would help you remove the malware from your computer. For example, if your computer is infected, you may be unable to access McAfee's website (because the virus doesn't want you to download software that you can use to remove it).

How does malware get installed?

There are many ways your computer can become infected by malware.

Infected Files - One of the most common ways for a virus or other malware to infect your computer is through infected files. For years, viruses have been delivered to unsuspecting recipients through email. Avoid clicking on email attachments you weren't expecting to receive, even if they are from someone you know.
Instant Messaging - Some viruses can use instant messaging programs like AOL Instant Messenger (AIM) to infect others. An instant message sent by a virus might say, "Check this out!" When your friend clicks the link, that person's computer is infected too. Be cautious about links sent to you in IM.
Web Page - Malware can get installed to your computer when you visit a web page. Some web pages might exploit vulnerabilities in your web browser to install malware on your computer without you even knowing about it. Other web pages might prompt you to install something when you visit the page and unless you realize what you're being asked, you may unwittingly install the malware.
Piggyback - Sometimes when you install an application, malware is installed too. This might be because the software vendor has made a deal with the malware vendor. In cases like this, the installer may ask if you want to install the second application (i.e. the malware). Unless you recognize it for what it is, you may unwittingly install it to your computer.
Fake Security Software - Some of the "security" (anti-malware or anti-virus) software available on the Internet is actually malware in disguise. Like phishing scams, these fakes try to trick you into installing malware onto your computer by convincing you it's for your own good.
Fake Cool Program - Some "cool" programs you install are actually malware. Cute programs that supposedly "enhance" your web browser or alter your system's appearance may actually be malware. Like the story of the Trojan Horse, this malware entices you to install it by making you want it. Once the malware is on your system, its negative effects far outweigh any supposed benefits.
Shared Folders - Some viruses scan the network for unprotected shared folders. If your computer has a shared folder that's not password protected, it could be an open doorway for a virus. You should always make sure shared folders on your computer are protected.
System Vulnerabilities - Some viruses look for computers that have vulnerabilities. If a virus finds a vulnerable computer, it can exploit the machine to infect it. To protect your computer, you should always stay up to date with critical system updates for your operating system and web browser.

Protecting Against Malware and Viruses

To protect your computer against malware, you should use a combination of anti-virus software, anti-spyware software, safe habits, and common sense.

Install the University-approved anti-virus software.

Your computer should have the university-approved anti-virus software installed, and it should be configured to automatically update. McAfee VirusScan is required for all Windows computers connected through the campus network. McAfee Security for Mac is the required anti-virus product for Mac OS X.

McAfee VirusScan is the university-approved anti-virus software for four reasons:

Anti-virus and Anti-spyware - McAfee VirusScan for Windows and McAfee Security for Mac both protect your computer from viruses, spyware, and other malware. This dual level of protection is important because spyware and other forms of malware are becoming as prevalent as viruses.
ePO Updates - Student computers on ResNet and faculty/staff computers in campus offices are centrally managed by the campus ePolicy Orchestrator (ePO) server, which makes sure McAfee VirusScan updates are promptly delivered.
Efficiency - It is more efficient for the University to support a single anti-virus application for each operating system than to support several anti-virus applications, such as Norton, Sophos, AVG, TrendMicro, etc.
No Cost to You - The University has paid for a site license for McAfee VirusScan and McAfee Security for Mac, which means that all Illinois State students, faculty, staff, and retirees are authorized to use the product for free.

You may download McAfee VirusScan for Windows and McAfee Security for Mac for Mac OS X from the Help Desk website (valid ULID and password required).

Install and use additional software.

In addition to McAfee VirusScan, you should consider the following additional software for your Windows computer.

MalwareBytes Anti-Malware - This excellent product scans for infected files and helps you clean your computer. MalwareBytes Anti-Malware can find and remove viruses, spyware, and other malware.
CCleaner - CCleaner scans temporary folders and the registry for unwanted items. It can also prevent unwanted programs from running when Windows starts up.

Both of these products are routinely used at the TechZone Service Center to clean infected computers. You may download MalwareBytes Anti-Malware and CCleaner through the Help Desk website.

Install critical system updates.

If your computer alerts you about the availability of new critical system updates, you should install them—don't ignore them. Malware can exploit your computer's vulnerabilities. By installing critical system updates, you patch the holes in your computer that can be used by malware. This is key to protecting your computer against Internet threats like viruses, spyware, and other forms of malware.

Think before you click.

Like phishing scammers and identity thieves, malware often relies on human interaction. For example, if you receive an email with a virus attachment, the virus can't harm your computer unless you click on it. If you visit a web page that prompts you to download a "plugin" (which is actually malware in disguise), it can't infect your computer unless you download and run the file.

Avoid unsafe websites.

Some forms of malware, including some viruses, do not need your permission or interaction to infect your computer. The best way to avoid that kind of malware is by using safe habits. Avoid visiting websites that might exploit your computer. For example, avoid searching for things like "free MP3s," "free screen savers," and other "free" software that is not normally available at no cost (like "free Windows 7" or "download Photoshop").

Peer-to-peer downloads can be dangerous.

Avoid using peer-to-peer software to download files when you are unsure if it is a trustworthy source. For example, World of Warcraft updates are distributed using peer-to-peer, so that is trustworthy. Linux is often distributed using peer-to-peer as well, and those sources can generally be trusted. However, if you are downloading an application, game, song, or movie from an unknown source, the file could be infected with malware. Stay away from downloads like that to avoid potential harm.