Cyber Viruses

Top 7 Most Dangerous Cyber Viruses

Cyber Viruses

Computer viruses are programs designed to carry out nefarious activities. It may steal personal data, delete confidential files, or adversely affect how your hardware works. Virus is a general term, used to describe all of these bad programs. However, there are other terms you may or may not be familiar with, such as malware, Trojans, spyware and the like, all of which are used to describe computer viruses. In addition to that, there are many other terms, maybe not as widely known, but do exist.

Below, you will find a list of computer virus terms that you should be aware of.

  1. Backdoor Santa

The vast majority of computer users download apps from third-party sources. A Backdoor Santa is a little app that is designed to collect data on you, such as, the apps you may be running, or the websites that you visit, along with the products you like to purchase. All of which happens without your knowledge. Which is the purpose of the virus, to do its job in silence.

That aside, there are some backdoor programs that many users install purposefully. For example, browser toolbars; which are designed to collect information on your very own web searches.

  1. Bots

A bot is a piece of self-replicating software that spreads across various devices creating its very own network of bots, which are referred to as botnets. Once a system has been infected with this malware, it will then carry out tasks, commanded by the hacker. Botnets are most often used for DDoS attack types. However, they are also used in phishing emails and keylogging.

A most notable example of a botnet would have to be Mirai. This malicious software was originally launched in 2016, in the form of a DDoS attack. Today it continues to target IoT and related devices. Research has also shown that botnets flourished during the recent pandemic. Consumer devices tend to be the most common targets of Botnets and the Mirai virus. This is because of the activity end users are typically engaged in while on their systems.

  1. Keyloggers

Keyloggers are essentially spyware. Viruses that are designed to monitor your keystrokes. Computer hackers will oftentimes use keyloggers to obtain the usernames and passwords of their victims – along with other sensitive information.

A keylogger can be software or hardware. Hardware keyloggers are installed manually into a keyboard. After the victim uses the keyboard, the cybercriminal must have direct physical access to the keyboard to retrieve the data. However, when it comes to software keyloggers, physical access is not required to obtain such data. Keyloggers are most often downloaded by the actual victim, via a program download or malicious link. The keylogger will then record all keystrokes and send it to the hacker.

The spyware RAT has been around for a significant length of time, still causing havoc across the internet, with its latest iteration being able to take screenshots of its victim’s devices in addition to logging its keystrokes.

If you want to inhibit these keyloggers, then you can’t go wrong with password managers. They are especially helpful because the user is no longer required to manually fill in their username and passwords, thus making it impossible for the keylogger to record the user’s strokes.

  1. Rootkits

A rootkit is another piece of malicious code used to give remote access to a victim’s machine, with all the correct administrative rights. A rootkit can be injected directly into a piece of firmware, app, or kernel. They most commonly spread through email attachments (via phishing) malicious downloads and compromised USB sticks. A rootkit can also be used to hide other viruses, such as keyloggers.

For example:

Zacinlo is a virus that infiltrates its victim’s machine every time they download a fake VPN app. Once it gets onto the user machine, it carries out a quick security sweep to locate any other malicious files on the system, quietly removing whatever it finds. After which, it will open up your browser and start to interact with different content, just as any user would, by highlighting, scrolling and clicking.

The purpose of this activity is to fool any security tool designed to monitor user behaviour patterns. The full brunt of Zacinlo is only felt when an end user clicks on a malicious ad within their browser. This advertising click fraud can provide all actors involved with a quiet some of cash.

  1. Diallers

A dialler is a small piece of malicious code that is used for making internet connections through your modem device without user permission. In most cases it will open up porn or offensive sites. This attack type is only affective on users who access the internet directly through their phone connection.

  1. BHO

Browser Helper Object or BHO, gets to work immediately after the end user opens their browser. Though, a large number of BHOs are actually helpful, there are a number of them that will redirect you to undesirable sites, such as porn sites. Once it has successfully taken control of your system, you will notice it start to work much slower. Many Trojan horse viruses like to use BHO to carry out their activities.

  1. Spyware

Spyware is a type of virus that installs itself on a user’s device with his/her permission. It then proceeds to steal the information on the device so that it can sell it to advertisers and other external users willing to buy it.

Spyware is capable of tracking credentials and acquiring sensitive data such as bank details, usernames and passwords. It gets onto devices through malicious links, apps, email attachments and websites.

There are also mobile device based spyware that is able to spread through SMS and other messaging services. It can be very damaging, primarily because it will track the location of the user, while being able to access both the microphone and the camera of the device. Keyloggers (as mentioned earlier), adware, and Trojans are just a few of the many different forms of spyware out there.

Pegasus is one of the most notable mobile based spyware, used for targeting Android and iOS devices. It was first introduced to the public in 2016, during which time, it was originally linked to technology vendor NSO Group based in Israel. A lawsuit was filed in November 2021 by Apple, for the virus attacking products and customers of Apple. Pegasus also had links with the assassination of a journalist based out of Saudi Arabia, in the year 2018.


Uchenna Ani-Okoye is a former IT Manager who now runs his own computer support website