Phishers develop sophisticated lure

Covert scripting exploit

By John Leyden, 4th November 2004

Fraudsters have developed phishing emails capable of automatically stealing bank log-in details without requiring users to click on a website link, email filtering firm MessageLabs warns.

Over the last two weeks, MessageLabs has monitored a small number of these dangerous new emails, which are capable of sidestepping the need for user intervention in phishing attacks. Users who only open maliciously constructed emails to be exposed to risk. These emails contain scripts that rewrite the host files of targeted machines. This means that next time a user attempts to access their online banking account they will be automatically redirected to a fraudulent website instead, enabling their log-in details to be stolen. So far, MessageLabs has only intercepted copies of emails targeting three Brazilian banks, but if the technique catches on it could have potentially serious consequences.

A defence is available. Providing surfers have Windows Scripting Host disabled they are not at risk from this particular type of phishing attack. MessageLabs said the technique illustrated the increased sophistication of phishing techniques fraudsters are developing.

Alex Shipp, senior anti-virus technologist at MessageLabs, said: "By reducing the need for user intervention, the perpetrators are making it easier to dupe users into handing over the contents of their bank accounts. Most banks have advised their customers to be wary of any email asking for personal banking details, but in this case all they have to do is open an apparently innocent email and their bank details could be silently sabotaged.

"We currently detect between 80 and 100 new phishing websites a day, showing just how prolific the threat has become. It is a moving target, making it harder to identify and defend against," he added. ®