Vulnerabilities have been revealed in multiple Microsoft applications, leading to an emergency ‘out-of-band’ security update advisory. Here’s what you need to know.

The second Tuesday of each month, known colloquially as Patch Tuesday, is when Microsoft releases a swathe of security updates to users of the Windows operating system. The most recent of these, distributed on April 14, included no less than 133 vulnerabilities across a range of Microsoft products.