A Trojan targeting Mac computers in the wild used to be a rarity, but this type of malware is now turning up with alarming frequency. The latest Trojan is rudimentary, at best, although when coupled with a Mac platform vulnerability that came to light earlier this week, it could deliver an extra wallop. The Trojan is masquerading as a program for Mac OS X called “PokerGame.” All in all, it’s pretty straightforward — both in the way it installs itself and in how it’s executed. It is a social engineering-designed hack attack at its most basic.