Hackers are achieving new levels of automation using software tools, zombies and bot nets to "vastly increase the potency" of their fraudulent campaigns, according to analysts.

The Anti-Phishing Working Group (APWG) reports that "disturbing" shifts in phishing techniques have been detected, indicating that attacks are becoming increasingly automated and sophisticated.

Starting in early October, APWG analysts witnessed "massive increases" in the amount of phishing sites, mostly outside the US, indicating that a new and powerful set of tools might have been deployed recently.

Moreover, the group noted that the number of sites being hosted on what appear to be compromised PCs has risen to more than 50 per cent.

Dan Hubbard, senior director of security and technology research at security firm Websense, said that some automation, such as the use of a bot network to either send more emails and/or host more sites, would probably be needed to account for the increase.

The number of brands subjected to the largest numbers of phishing attacks rose from four in July to six in October, indicating a broadening of attack subjects, John Thielens, chief technology officer at Tumbleweed Communications, wrote in APWG's Phishing Activity for October report.

The full text of the report is available as a PDF here