The Inqtana worm exploits a vulnerability known as CAN-2005-1333 to spread itself to other vulnerable Mac OS X computers, but Apple released a patch against the vulnerability in mid 2005, meaning the worm is highly unlikely to spread successfully. OS X users have been urged to keep their software updated against the latest security vulnerabilities in Apple's code.
"It's disturbing to see a second worm for OS X so soon after the first, but it should be remembered that this is only two compared to well over 100,000 viruses for Microsoft operating systems," said Graham Cluley, senior technology consultant for Sophos. "The good news is that Inqtana is not going to spread successfully in the wild, but this announcement will still be a shock to those in the Mac community who thought hackers were not interested in their operating system."
A report issued by Sophos last week revealed that 79 percent of people believed that Macintoshes would be targeted more in future, following the discovery of the first Mac OS X worm.
"The question on everyone's lips is - when will we see the next one, and will it have a more malicious payload," said Cluley. "Apple Mac users need to be just as careful about protecting their computers with anti-virus software, firewalls and security patches as their friends and colleagues using Windows."