What is Malware? Common Malware Types

Iain Roberts by Published On - 04.04.2022   Data Security

What is Malware

Malware is malicious software that is designed to cause disruption to an IT system, leak private information, or extort the victim in some way. As you can imagine, organizations are very keen to protect their systems from malware attacks due to the costs associated with them. However, given that most malware attacks are the result of human error, there aren’t yet any fool-proof techniques for preventing them.

Once a system has been infected with malware, any number of undesirable events can unfold. To make matters worse, some forms of malware operate in a very covert manner and are thus able to go undetected for several months, perhaps even longer.

Malware typically arrives in the form of an email attachment, although in some cases the victim will be sent a link to a malicious website, where they will be tricked into downloading/executing a script or handing over their credentials. Anyone can potentially fall victim to a malware attack, including IT professionals, as all it takes is one accidental click.

While reports have suggested that some types of malware are on the decline, ransomware, phishing sites, cryptojacking and IoT malware are on the rise. However, it’s worth noting that in the wake of the pandemic there was a surge in the number of malware infections, as cybercriminals saw it as an opportunity to exploit vulnerable employees. As organizations continue to adapt to such changes, their defense against malware attacks will inevitably improve.

The Most Common Types of Malware Attacks

1. Adware

Adware is a type of malicious software that displays unwanted advertisements on your computer. Although it is relatively harmless, it can be very annoying for the victim, and many adware programs will slow down the victim’s computer. In some cases, the adware will install other malware programs in the background, such as viruses or spyware.

2. Viruses

A virus is a general form of malware that is designed to infect your system and then spread to other systems. Viruses typically arrive in the form of an email attachment, and once executed, can corrupt, encrypt, steal or delete the files on your system.

3. Worms

A worm is a type of malware that is designed to copy itself and spread from one computer to the next, and it can do so without any human interaction. In many cases, the worm script will simply replicate itself in order to deplete a system of its resources. Worms can also modify and delete files, as well as install additional forms of malware onto the system.

4. Trojans

A trojan derives its name from the legendary “Trojan Horse”, which instead of being a gift, turned out to be malicious. Unlike a virus or a worm, a trojan relies on the user to execute the application and usually arrives via social engineering.

5. Bots

Bots are small programs that perform automated tasks, often without the need for human intervention. Bots are often used to perform distributed denial of service attacks (DDoS), which is where the bots are installed on a large number of devices, often without the device owner’s knowledge. Hackers then use these bots to launch a large-scale attack on a given target, which includes flooding the target with traffic in an attempt to cause disruption.

6. Ransomware

Ransomware is arguably the most formidable form of malware, perhaps because it is the most profitable. Once the ransomware script has been executed on the victim’s device, the script will begin encrypting their files. At which point, they will be presented with a message informing them that their files have been encrypted and that they must pay a ransom in order to get their files back. In some cases, the attackers will threaten to publicly release the victim’s files unless a payment is made.

7. Spyware

Spyware, as the name would suggest, is a form of malware that is designed to spy on its victims. A common use of spyware is to log the keystrokes of the victim or monitor their activity in some way to obtain credentials or some other type of personal information.

8. Fileless Malware

Unlike other forms of malware, fileless malware doesn’t rely on files to infect a victim’s device. Instead, it exploits tools that already exist on their devices, such as PowerShell, WMI, Microsoft Office macros, and more. Since fileless malware doesn’t leave a footprint, it is a lot harder to detect.

If you’d like to see how the Lepide Data Security Platform can detect and react to malware, schedule a demo with one of our engineers or start your free trial today.