Experts crack nasty ransomware that locks your PC and your backup

Sometimes even CHKDSK isn't safe.

Petya, a brutal piece of malware, surfaced two weeks ago. It's a mean bit of crypto-extortion that hits its victims where it hurts: right in your startup drive. Because it encrypts your master boot file, if attacked, not only will you be unable to start up your PC and not even access your startup disk. Eeesh. Fortunately, there's help. Leostone has come up with a tool that creates the password needed to unlock your startup disk. It's not all that simple, however.

You'll need to remove the startup drive and connect it to a separate (not infected) Windows PC, and then pull some specific bits of data to plug into this web app — and craft your password. (There's also another free tool that can grab the necessary data nuggets here.) From there, you'll be able to decrypt that all-important master boot file — and forever learn the lesson of vigilance when it comes to possibly fake CHKDSK antics.