Users may be forced to contact their IT suppliers to protect themselves.
The Trojan targets a computer's DNS server and adds a malicious entry that intercepts and re-routes web requests to malware-ridden and/or porn sites.
Preparing a defence against this malware will be difficult for Mac users because their operating system does not allow users to see that something is amiss. The user interface does not allow the owner to see that the DNS server has changed, explained UK security expert David Hobson, managing director for Global Secure Systems. He advises users manually configure their systems against this offensive code.
"Even with the latest versions of OS X, the changes are not obvious, as the added DNS entries are dimmed and cannot therefore be directly changed," he added. He also urged mac users to consult their IT supplier to ensure their products are protected against this potentially serious malware.