A multi-national task force led by the FBI have announced that they have successfully taken down the botnet known as Qakbot. The botnet was used for a variety of cybercrimes, resulting in losses of hundreds of millions of dollars to individuals and businesses. You can read about it here.
But what is a “botnet”?
Botnet is a portmanteau word of robot and network. Simply put, it is a group of computers that hackers have infected with malware, turning them into an army of unwitting zombie computers. This army can then be remotely controlled by the hackers to commit cybercrimes, using the combined power of hundreds of thousands, or even millions of zombified computers. Beyond the zombified computers working a bit harder than normal, or above normal electricity and internet usage, there are often no visible signs to the owners of the computers.
If you are “lucky”, your zombified computer might only be used as a part of a global crypto-currency mining operation. But it could also be used as a participant in massive malicious email campaigns or be part of giant cyber-attacks. Some of the malware used additionally gives the hackers the bonus of stealing passwords and data from the zombie computers.
In the case of Qakbot, it is believed that some 700,000 computers, spread across the world, had been co-opted into the botnet via malicious spam emails.
Qakbot’s size is dwarfed by previous botnets. It’s believed that the Russian botnet BredoLab consisted of some 30 million zombie computers, and was capable of generating 3.6 billion (yes, billion with a “b”) malicious emails per day.
How do I stop my computer being zombified into a botnet?
The good news is that you should be okay as long as you are already practicing good cyber hygiene. Have a good password, use 2FA (Two-Factor Authentication) wherever possible, run good anti-malware software, never click links in suspect emails, and don’t download software from dodgy web sites.
If you suspect that your computer is already infected, you should seek out the advice of your IT support person/team or contact an IT professional.