Blue Pill (software) facts for kids
Blue Pill is the special name for a type of computer program called a rootkit. Think of a rootkit as a hidden tool that can take control of a computer. Blue Pill uses something called x86 virtualization. Virtualization is like creating a "virtual" or fake computer inside your real computer.
This program was first made to work with a special feature from AMD computer chips, called AMD-V. Later, it was updated to also work with Intel chips that have a feature called Intel VT-x.
A computer security expert named Joanna Rutkowska created Blue Pill. She first showed it to the public on August 3, 2006, at a big computer security event called the Black Hat Briefings. At that time, it was shown working on computers running Microsoft Windows Vista.
The name "Blue Pill" comes from the 1999 movie The Matrix. In the movie, characters are offered a choice between a red pill and a blue pill. The blue pill lets them stay in their normal, but fake, world.
What is Blue Pill?
The main idea behind Blue Pill is to trick a computer's operating system. An operating system is the main software that runs your computer, like Windows or macOS. Blue Pill does this by starting a tiny, hidden program called a hypervisor. This hypervisor then takes over and makes the computer's original operating system run inside it, like a virtual machine.
Imagine your computer is a house. The operating system is like the owner. Blue Pill builds a secret, invisible room around the house. Now, the owner (operating system) thinks they are still in their house, but everything they do, like opening a door or checking the time, actually goes through the secret room first. This means the hypervisor can see, change, or even stop anything the operating system tries to do. It can even give fake answers to the operating system's requests.
This idea was first talked about by another researcher in May 2006. They called it VMBR, which stands for "virtual-machine based rootkit."
Can Blue Pill Be Detected?
Joanna Rutkowska believed that Blue Pill could be "100% undetectable." This is because the hypervisor could trick any program trying to find it. Since the way AMD's virtualization works is designed to be very smooth, a virtual computer isn't supposed to be able to tell if it's virtual or real. So, the only way to find Blue Pill would be if the virtualization system itself wasn't working perfectly.
However, not everyone agreed with this. AMD, the company that makes the computer chips, said that Blue Pill could be detected. Other security experts and journalists also thought it was possible to find it. For example, they suggested using a "timing attack." This is a method that checks how long certain computer tasks take. If they take longer than expected, it might mean a hidden program like Blue Pill is interfering.
In 2007, some researchers challenged Rutkowska. They wanted to test Blue Pill against their software designed to find rootkits at the Black Hat conference. But the test didn't happen because Rutkowska asked for a lot of money ($384,000) to take part. Later, Rutkowska and another expert, Alexander Tereshkin, argued that the suggested ways to detect Blue Pill were not accurate.
The computer code for Blue Pill has since been made public. It was shared for educational purposes during the Black Hat training and conference.
Red Pill
Red Pill is another computer technique that was also developed by Joanna Rutkowska. But instead of hiding, Red Pill is used to find out if a computer is running inside a virtual machine. It's like the opposite of Blue Pill.
