Explore a range of common cyber security threats — find out how they work, how to prevent them, and what to do if they happen to you.
Malware aims to go unnoticed — to gain access to your computer without you knowing it's there. It’s generally used:
Viruses may enter your computer system when you download an infected file or visit an untrustworthy website. They’re usually attached to files you:
When a virus gets into your computer it can spread through your programs and files, corrupting them and causing your computer to either slow down or even stop working altogether. Having a virus in your computer system can make it more vulnerable to other attacks, like ransomware.
Worms are a kind of malware that can enter your computer system through:
Just like a parasite, a worm requires the host — in this case, your computer — to be operating to spread. Once they’re in your system they can move quickly and easily through lots of computers on a network, whether it’s a local network (LAN) or a global network (WAN). Worms can also damage your files and programs, and leave you vulnerable to other forms of attack.
Trojans are another type of malware. Just like the Trojan horse of Troy, they hide inside legitimate objects — for example, files like Word documents or PDFs — until someone opens them. When they get into your system, they can give others access to your computer without your knowledge. If other people get access to your computer they can download more malware, like worms, from the internet. Trojans themselves don’t spread over networks, but the other malware they download can.
Spyware and adware work by passing information to third parties about your behaviour online. This allows them to target you with advertising for products and services, whether you’re interested in them or not. Some of this content can be offensive, which can indicate that you have spyware or adware on your computer.
Adware monitors the websites you visit and pushes ads onto your device. It can choose ads that you’re likely to click on, or ads that would embarrass you. These ads can appear within a site or as popup windows. Adware can cause problems when:
Spyware gathers information about the system it infects. It:
It can even track the information you type into websites. In some cases, this means that personal or sensitive information — like your internet banking details — can be accessed and used without your knowledge or consent. This is called keylogging.
Malware’s easier to avoid than it is to fix. Here’s what you can do to reduce the likelihood of an infection.
If you think your computer’s infected with malware, talk to your IT support person or a local computer services company. They can:
There are a lot of free antivirus, antispam and antispyware products on the market. Not all of them are legitimate though, so it’s important to discuss your options with an IT professional before installing one on your computer yourself. They can help you work out what product’s best for your needs. While there’s no foolproof way to prevent malware infections, these products will help protect your computer system from them.