MICROSOFT HAS ISSUED a patch to fix a major flaw in Windows that has existed in every version since Windows 95 was released.

The flaw, which has been around for almost 19 years, was discovered by IBM security researchers earlier this year and had notified Microsoft privately in May.

The bug lies in a security package called Secure Channel (Schannel) which is used by Internet Explorer.

While there has been no evidence that it has been exploited yet, the flaw allows attackers to remotely take over a user’s machine just by convincing Windows users to visit a website through Internet Explorer.

“In some respects, this vulnerability has been sitting in plain sight for a long time despite many other bugs being discovered and patched in the same Windows library,” said Robert Freeman in a post detailing the discovery.

While Microsoft is providing patches for Windows 8.1, Windows 7, Windows Vista and other releases, it stopped supporting Windows XP earlier their year meaning anyone using it won’t be covered if attackers try to exploit this bug.

If you’re using a Windows computer, it’s recommended that you visit Control Panel and run Windows Update to make sure everything is up to date.

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