Experts at Check Point security firm analyzed the recent data breach suffered by Anthem, the nations second-largest health insurer. The breach was designed to stay below the radar of the IT and security teams, using a bot infection to smuggle data out of the organisation. The first signs of the attack came in the middle of last week, when an IT administrator noticed a database query was being run using his identifier code when he had not initiated it. An independent security consultancy reports that the attack may have been started up to three months earlier.”]
Source: http://securityaffairs.co/wordpress/33582/cyber-crime/anthem-breach-slow-silent-attack.html