Microsoft has issued an urgent advisory notice recommending that Windows users immediately install an update to fix a serious vulnerability.
The security flaw, known as PrintNightmare, affects the Windows Print Spooler service. Researchers at cybersecurity company Sangfor accidentally published a how-to guide for exploiting it.
The researchers tweeted in late May that they had found vulnerabilities in Print Spooler, which allows multiple users to access a printer. They published a proof-of-concept online by mistake and subsequently deleted it — but not before it was published elsewhere online, including developer site GitHub.
Microsoft (MSFT) warned that hackers that exploit the vulnerability could install programs, view and delete data or even create new user accounts with full user rights. That gives hackers enough command and control of your PC to do some serious damage.
Windows 10 is not the only version affected — Windows 7, which Microsoft has ended support for last year, is also subject to the vulnerability.
Despite announcing that it would no longer issue updates for Windows 7, Microsoft issued a patch for its 12-year old operating system, underscoring the severity of the PrintNightmare flaw. Updates for Windows Server 2016, Windows 10, version 1607, and Windows Server 2012 will are “expected soon,” it said.
“We recommend that you install these updates immediately,” the company said.
If there’s any good news is that the current security update is cumulative, meaning it contains previous fixes for previous security issues too.
It’s the latest in a slew of security alerts from Microsoft in the past year and a half.