The dreaded 'Blue Screen of Death' helped save some PCs from massive ransomware hack

Lulz.

While the WannaCry ransomware that swept across the world and crippled hundreds of thousands of PCs ransomware last month isn't really a laughing matter, what is hilarious is how Windows' infamous, dreaded, face-meltingly awful "Blue Screen of Death"—the error message that appears after a PC's crashed—managed to prevent computers from being infected.

Contrary to original reports, the majority of computers WannaCry-infected PCs were not in fact running Microsoft's outdated Windows XP, but actually Windows 7, according to a recent Kaspersky Lab analysis.

Despite Windows XP computers contributing to an "insignificant" percentage of total infected PCs—98% of PCs infected with WannaCry were running some version of Windows 7—the damage could've been worse, had it not been for the Blue Screen of Death (BSOD).

According to new research from the cybersecurity experts at Kryptos, installing WannaCry on PCs running Windows XP isn't as effective as previously believed.

In tests on various versions of Windows, researchers discovered that repeated attempts to infect machines with WannaCry merely caused them to crash (displaying the BSOD) and require a hard reset, instead of encrypting all the computers' files in return for a ransom.

"To be clear, the Windows XP systems are vulnerable to ETERNALBLUE, but the exploit as implemented in WannaCry does not seem to reliably deploy DOUBLEPULSAR and achieve proper RCE, instead simply hard crashing our test machines," Kryptos said in a blog post. "The worst case scenario, and likely scenario, is that WannaCry caused many unexplained blue-screen-of-death crashes."

Windows XP PCs aren't completely immune to WannaCry (manually installing it will do the trick), but at the very least, the BSOD seems to get in the way of the ransomware doing its job locking up systems.

It's ironic, that the last thing any PC user wants to see managed to save the day. If you'd asked anyone if there was ever a situation in which they'd want to see the Blue Screen of Death, you'd be hard-pressed to find an answer. Until now.

That said, if you haven't already updated your PC with the latest security patch, or better yet, to Windows 10, you should definitely consider it. It's better to not take any chances when it comes to your computer's security—granted, some users can thank their lucky stars for it, but relying on the Blue Screen of Death isn't exactly an ideal way to go about securing your computer.