"There are more eyes looking over Apple products for vulnerabilities," Hotchkies said.
"It has slowly been growing as a target people are more and more interested in."
ZDI specializes in Apple software and is devoted to making "patches" for security holes.
"There are a lot more people getting into it and really getting their hands dirty," said Hotchkies, who added he saw an increase in Mac-toting attendees at the Defcon event.
"I've been seeing a lot of reverse engineering on the Apple platform."
Hotchkies attributes a lot of the increased popularity on the fact that Apple has made their machines friendlier to programs that can run on Windows machines. Hackers that can attack Windows programs can now more easily attack software that has been modified to run on Macs, not completely written for it.
"Windows developers take their code and make it work on Apple," Hotchkies added. "They could take potential vulnerabilities with them or possibly create new ones because they are working on an entirely different platform."