Proofpoint firm uncovered a malicious campaign run by the Northern Gold criminal group which is targeting online banking users with a botnet of 500,000 PCs. The Northern Gold group is using Qbot malware to infect victims systems. The large botnet syphoned conversations, including account credentials, for roughly 800,000 online banking transactions. Internet Explorer is the most targeted browser in the campaign. Majority of infected machines runs on Windows XP (52 percent) meanwhile Windows 7 PCs account for 39 percent of infected clients.”]
Source: http://securityaffairs.co/wordpress/29006/cyber-crime/northern-gold-half-million-pcs-botnet.html