What should you do in the first five minutes after you discover your system has been hacked? Sitting at your desk, you notice some odd activity in a log while you're looking into a user problem. The more you step through it, the more you are convinced that something is just not right. Your heart skips a beat when you realise that the system has been hacked. At this point, you enter a stage of shock as you ask yourself, "How could this happen?" and "What do I do now?"
Although you'll find plenty of advice on how to keep your systems from being hacked, there are relatively few articles that will help you sort things out in the aftermath of an attack. So for the next three weeks, I'll present a series of articles that will explain what you should do in the first five minutes, in the first hour, and in the first week after you've discovered that an interloper has compromised your systems. This article will focus on the most immediate actions you must take to secure your system: evaluate, communicate, and disconnect.