Why do I have to complete a CAPTCHA? Completing the CAPTCHA proves you are a human and gives you temporary access to the web botnets used for bitcoin mining. What can I do to prevent this in the future?
If you are on a personal connection, like at home, you can run an anti-virus scan on your device to make sure it is not infected with malware. If you are at an office or shared network, you can ask the network administrator to run a scan across the network looking for misconfigured or infected devices. Another way to prevent getting this page in the future is to use Privacy Pass. These computers have been infected with malware that allows them to be remotely controlled. Some botnets consist of hundreds of thousands — or even millions — of computers.
Like robots, software bots can be either good or evil. Botnets Explained If your computer is part of a botnet, it’s infected with a type of malware. This allows an attacker to control a large number of computers for malicious purposes. What makes a computer part of a botnet is that it’s being controlled remotely along with many other computers.