SecureMac.com has issued a security advisory for users of Apple’s OSX. The site discovered “multiple variants” of a Trojan horse in the wild that affects users of OS 10.4 and 10.5. The Trojan was first discovered on a hacking website which included instructions on how to distribute it via iChat and Limewire.

Okay, nerds, here’s some info that you’ll appreciate:

The Trojan horse runs hidden on the system, and allows a malicious user complete remote access to the system, can transmit system and user passwords, and can avoid detection by opening ports in the firewall and turning off system logging. Additionally, the AppleScript.THT Trojan horse can log keystrokes, take pictures with the built-in Apple iSight camera, take screenshots, and turn on file sharing. The Trojan horse exploits a recently discovered vulnerability with the Apple Remote Desktop Agent, which allows it to run as root.

The Trojan is distributed as either a compiled AppleScript, called ASthtv05 (60 KB in size), or as an application bundle called AStht_v06 (3.1 MB in size). The user must download and open the Trojan horse in order to become infected. Once the Trojan horse is running, it will move itself into the /Library/Caches/ folder, and add itself to the System Login Items.

As I expected, the growing popularity of Apple computers has made them a more attractive target for virus writers. Any readers with Macs feel compelled to pick up Norton’s Anti-Virus? Comment and let us know.

(source)