Pieces of fresh Mac malware increased significantly in 2011, further debunking the myth that cyber criminals are not turning their attention to Apple machines.
There were 58 new Mac threats between April and December 2011, F-Secure analysis found.
"That's nothing when compared to Windows malware - but it's definitely something when compared to the number of Mac threats seen prior to 2011," F-Secure said in a blog post.
Most Mac threats were Trojan-downloaders, with 29 appearing over the nine month period.
Backdoors came in second on 15, with Trojans and rogue AV taking seven each.
There were noticeable spikes in June and October, as F-Secure's graph below shows.
"Mac malware has not scaled continuously due to market share, but rather, is more the result of opportunist 'bubble economies' that have produced new threats in fits and starts," F-Secure added.
"We expect more of the same for 2012."
Security professionals believe Mac malware will increase again this year, as awareness amongst users is growing.
"Fortunately enough, it seems that Mac users are now more aware that Mac is not immune to malware attacks and they are increasingly using antivirus programs, hindering cyber-crooks," said Luis Corrons, technical director of PandaLabs, in a blog post.
"The number of malware specimens for Mac will continue to grow in 2012, although much less than for PCs."