Earlier this week, Apple uploaded a security update that aimed to fix the Mac Defender malware that had been causing problems for some Mac owners over the last few weeks. The update is available through the update services in OS X. When installed, it gets rid of the Mac Defender malware and also scans for variants of it.
Within 8 hours of the security update going live, a new variation of Mac Defender had been created which bypassed the new security restrictions that Apple put in place.




