Last month the attacks rose by 6 per cent, which is the lowest level this year.
According to research from the Anti-Phishing Working Group, ninety-five per cent of attacks relied on the use of forged sender addresses to hide the identity of the scammers and evade spam filters.
"The problem is that for the most part, email servers haven't cared where an email message claims to be from - they'll accept anything," said Dave Jevans, Chairman of the Anti-Phishing Working Group and Senior Vice President at Tumbleweed Communications. "Once ISPs start to verify the source of messages, a lot of the bad things in email, including phishing, will stop. Not many scammers will use their personal email accounts to launch a crime wave."
In May, there were 1197 new phishing attacks reported to the group. This was a relatively minor increase over the number of attacks reported in April (1125). The average number of phishing attacks per day in May was 38.6, up slightly from the 37.5 per day for April.
The company most-targeted by phishing attacks in May was Citibank with 370 unique attacks. This was down from 475 in April.