Malware: How it Sneaks In and What it Does to Your PC or Mobile

Here’s what happens when you get malware on your computer, cell phone or tablet: Internet Scambusters #943

Malware is the number one cause of security problems on home computers, cell phones, and tablets.

But the way it affects your device depends on its role and how it got there.

In the first of our two-part series, we identify the different types of malware and the tactics crooks use to install it.

Let’s get started…


Malware: How it Sneaks In and What it Does to Your PC or Mobile


Malware. The word strikes fear into the hearts of computer and mobile users these days. And with good reason.

It can cause havoc with your computer system, steal your data, cost you a fortune or even take you completely out of action.

According to research website DataProt.net, 350,000 pieces of malware are detected every day, and there are likely more than a billion “live” versions out there right now. That doesn’t include the stuff we don’t even know about!

But what exactly is “malware” beyond a very simple definition that sets it as computer code that’s bad (“mal” means bad in French) for you? And how does it get onto your device to cause trouble in the first place?

In this, the first of two special issues exploring what is the biggest security threat to home computer and mobile device users, we’ll help you understand some of the many types and disguises scammers use to get to the heart of your machine.

Viruses and More

First, malware comes in all sorts of shapes and sizes. We used to group them under the single name “viruses,” a highly appropriate real-world term these days. But, in reality, there are several types you need to be on the lookout for — most of them names you’ll probably recognize.

Trojans: The name comes from the mythological term in which a wooden horse was supposedly used to conceal soldiers so they could be smuggled into the enemy camp. So it is with Trojan malware. It’s disguised as something innocent that sneaks into PCs and mobile systems. Once inside, it launches other malicious code, such as…

Ransomware: This appears as a pop-up on your screen, preventing any further access to your device until you pay for the unlocking key. Often, there’s no such key and you’re left with a useless device, unless you have a backup. Or, it leaves another payload behind after it’s removed such as…

Spyware: Like most spies, it can see you but you can’t see it. So it sits there watching your actions or hunting for confidential information. Then it sends regular reports to the crooks who put it there. Spyware, which is especially common on Android phones and tablets, may be used just to target spam or ads to you or it may steal everything your device knows about you and use it for identity theft. Whether it’s spying or not, it may also plant a…

Netbot: Crooks send out billions of spam and malware-infected mails, or use infected links on web pages, to recruit your computer into an automated network to help them do their dirty work. A netbot-infected computer means you’re actually helping the scammers do their work!

Worms: Unless you’re into helminthology (the study of worms, apparently) in a big way, the thought of these slimy, self-replicating creatures may already make you a little queasy. In your computer, worms copy themselves over and over again, spreading across your home network and attaching themselves to messages you send out.

Virus: Yes, it’s still used as a standalone term — meaning, in this case, computer code that injects itself into existing programs on your device, causing them to malfunction and spread to others.

Root kits: Particularly nasty troublemakers that bury themselves so deeply into your system (the “root,” if you will), are incredibly tough to find and remove. Restarting and even resetting your computer might not get rid of one.

Malware comes in other variants, such as key loggers (spyware that records your keystrokes — especially common on public-use machines) and adware.

How Did They Get There?

Many of these pieces of malicious code overlap or work together. But how do they get onto your device in the first place?

  • Clicking is the number one culprit. We’re talking about clicking or touching malicious email and SMS text attachments, and links in messages, on websites and on social media.
  • Sometimes, you don’t even need to click a link. It can be hidden on a seemingly innocent page and activated just by moving your mouse over or near it.
  • Crooks may also hack into your home network by using stolen passwords and more sophisticated break-in techniques.
  • They can access your device when you use it on an insecure public network or plant malevolent code on removable devices like SD cards and USB drives, as we reported last week.
  • Crooked app developers have been caught, hundreds of times, building bad code into otherwise seemingly-innocent programs.
  • Even people who a user thinks they can trust and whom they allow to use their devices have been known to install malware.
  • And, in business, disgruntled employees have sabotaged company networks.

The trouble is that malware developers are continuously changing and improving the effectiveness of their dirty work, making it challenging for even the most advanced security software to keep pace.

But you can do a lot to both spot and avoid it. And, even if you do get infected, all may not be lost as long as you know how to remove it. We’ll discuss these issues and give you the essential key actions to beat the crooks at their own game in next week’s edition of our malware special issue. Don’t miss it.

Alert of the Week

If you’re fortunate enough to have money to invest, scammers almost certainly have you in their sights.

So, you may like to tune into a great podcast launched by the US Consumer Financial Protection Bureau (CFPB). As well as highlighting various scam risks, episodes help you increase your investment savvy so that you know when something doesn’t add up.

Access CFPB’s inTuition Podcast here.

Time to conclude for today — have a great week!