Security firm Intego has discovered a new Trojan dropper targeting Apple's Mac operating system that is resilient enough to survive system reboots.
Intego reported finding the OSX/Crisis Trojan which can establish backdoor access to infected machines and installs itself using a stealthy installation process.
The malware reportedly targets Apple's Snow Leopard and Lion operating systems and has built in defences that protect it from reboots - meaning machines will remain infected until the malware is actively removed.
The malware's effect on infected machines depends on the users administrative permissions.
"If the dropper runs on a system with admin permissions, it will drop a rootkit to hide itself. In either case, it creates a number of files and folders to complete its tasks," wrote Intego researcher Lysa Myers.
"The backdoor component calls home every five minutes, awaiting instructions. The file is created in a way that is intended to make reverse engineering tools more difficult to use when analysing the file. This sort of anti-analysis technique is common in Windows malware, but is relatively uncommon for OS X malware."
OSX/Crisis is one of many new cyber attacks to have been discovered targeting Apple's Mac operating system. Prior to OSX/Crisis the Flashback malware was uncovered at the start of 2012. At its peak the malware was believed to have infected over 600,000 systems.
Kaspersky Labs' David Emm recently warned that the number of MacOS attacks will likely increase over the next few years.