How did intrusions go on for five years without being noticed?

The Shady RAT report from McAfee this week found that some sensitive organisations had been under attack for up to five years in some cases.

Back in June last year, ArcSight president and CEO Tom Reilly told me that he had met with the CEO of a company who had suffered 'the largest breach in history', and said that while his technology could not have stopped the breach, it could have stopped it going on for '18 months'. Read more.