An anti-virus vendor has found the first example of "scareware" for Mac users. Windows users are well used to this spam, where bogus security software tries to spook consumers into coughing up to "clean" their systems, now Mac users are being offered the same dubious benefits.

MacSweeper, which sells for US$39.99 through a website of the same name, is a rogue application that will "always find something to fix/clean, but the only way to do so is to buy the program," claimed F Secure's Patrik Runald on the company's blog.

"Even more telling that it's a scam is the fact that when you visit the MacSweeper site with a PC and click on 'Scan,' it will tell you that you have security vulnerabilities in folders that only exist on [the] Mac, like 'system_root/home," said Runald. "Fake? Oh yeah."

Additional clues about the application's illegitimacy, added Runald, are easy to spot. The MacSweeper website, for example, includes text under an "About us" heading that is a brazen copy-and-paste from the Symantec site.

MacSweeper.com, which was registered in November 2007, uses a domain name server based in Ukraine, according to a WHOIS search. The individuals who registered the domain, however, masked their identities using an anonymity service.

MacSweeper, said Runald, is a cousin to the Windows scareware dubbed Cleanator, just one of numerous rogue security programs on that platform that try to dupe users out of money and/or credit card account information by posing as useful software. Among the most notorious scareware applications on Windows: SpySheriff, WinFixer and IEDefender.

"What does the first Mac rogue application really mean?" asked Runald. "It means that ... Mac users will increasingly come under attack from bad guys. It doesn't mean that Mac is becoming less secure in and of itself. But it does mean that Mac users will have to watch out for social engineering tricks just like Windows users have had to do for years."

MacSweeper's creators have fired back a response on the F Secure blog claiming that the selling tactics were all the fault of its "selling partners." The response said that the company supported the Mac and that it "hearts to here (sic) that the program ... is said to be some kind of "Rogue application"" However, the blog post failed to address other points raised by Runald's blog.

Original reporting by Gregg Keizer, Computerworld (US online).