Miscreants have created a proof-of-concept sample of adware that targets Apple Mac OS X users. iAdware might, in theory at least, be silently installed onto Macs, running itself each time an application is loaded, anti-virus firm F-Secure reports. The malware takes advantage of unspecified security weaknesses in the OS to load itself as a system library without prompting users about what's going on.

The malware is notable for its rarity rather than its threat value, which remains minimal. There's hundreds if not thousands of ad-ware packages floating around that are capable of infecting Windows users with intrusive pop-up software that impairs system performance. iAdware is the first such application for Macs that we've come across. ®