What is a KRACK attack?
KRACK is a flaw in the multi-step handshake system that occurs between devices. With it, a hacker could take advantage of the vulnerability to eavesdrop on your Wi-Fi traffic.
What could a hacker snoop on?
A hacker with access to a KRACK attack would be able to see almost anything you shared over your affected Wi-Fi network. This includes stuff like chat/email histories, credit card numbers, passwords, photos, and more.
How does it work?
During the multi-step handshake exchange between your machine and your wireless router, the devices confirm with one another that you’ve got the correct password and encryption keys.
The encryption keys are supposed to change frequently during your interaction with the wireless router, but KRACK allows the same keys to be re-used again and again, which makes your connection easier to crack.
What devices are affected?
Almost any device that can connect to a Wi-Fi-enabled network is affected. This includes your wireless routers, your smartphones, your tablets, your computers, etc.
The security researchers who found the vulnerability say that Android and Linux devices are the most susceptible, but that doesn’t excuse macOS, iOS, and Windows devices among others. Some manufacturers, including Microsoft, have already released updates.