The worldwide cyberextortion attack has prompted Microsoft to take the unusual step of making security fixes available for older Windows systems. Before this, Microsoft had made fixes for older systems, such as 2001's Windows XP, available only to organizations that pay extra for extended support. But millions of individuals and smaller businesses still had such systems. Microsoft says now it will make the fixes free for everyone. The customer guidance page is here. Friday's attack was based on a Windows vulnerability that was purportedly identified by NSA and later leaked online. Microsoft released fixes in March, but computers that didn't run the update were subject to the ransom attack.
The attack, believed to be the biggest of its kind ever recorded, infected computers in scores of countries with what is known as "ransomware"—software that locks up the user's data and flashes a message demanding payment to release it. Britain's national health service fell victim, its hospitals forced to close wards and emergency rooms and turn away patients. Russia appeared to be the hardest hit, cybersecurity experts say. The European Union's police agency, Europol, says it is working with countries hit by the attack to rein in the threat and help victims. The attack "is at an unprecedented level and will require a complex international investigation to identify the culprits," the agency says. (Read more cyberattack stories.)