Microsoft issues urgent warning for users to update PC

Microsoft is telling Windows customers to immediately install an update, after a serious vulnerability in the operating system was found by researchers.

The security flaw, known as PrintNightmare, affects the Windows Print Spooler service, according to CNN.

Researchers at cybersecurity company Sangfor accidentally published a how-to guide for exploiting it, the cable TV news network also reports.

The researchers tweeted in late May that they had found vulnerabilities in Print Spooler, which allows multiple users to access a printer, CNN also reports.