"In the coming days, Apple will deliver a Mac OS X software update that will automatically find and remove MacDefender malware and its known variants." Apple said in the support document it published Tuesday. "The update will also help protect users by providing an explicit warning if they download this malware."
Only Snow Leopard has rudimentary antivirus capabilities, which can warn users of a small number of threats. That same feature can also quarantine already-downloaded files that it deems dangerous.
But Apple seems to be saying that it will add a cleaning tool to Snow Leopard that can scrub an already infected Mac. If so, that would be a first.
And it would mean that Apple would be following in the footsteps of Microsoft, which has offered free cleaning tools -- notably the Malicious Software Removal Tool, or MSRT -- for years. MSFT is updated at least once each month, then pushed to customers via the Windows Update service.
People running older versions of Mac OS X, including 10.5, aka Leopard and 10.4, the even older Tiger, presumably will be on their own.
How pervasive is MacDefender? No one really knows.
A back-of-the-envelope estimate by Ed Bott, a ZDNet blogger who usually writes about Windows but has dealt out a series on MacDefender, put the number of infections between 60,000 and 125,000.
While security firms that sell Mac antivirus software have not tossed out numbers like that, at least one -- Intego -- has cited Bott's estimates and concluded that "this fake antivirus has been extremely effective in tricking Mac users."
Today, Finnish antivirus company F-Secure said it had seen "a significant rise on infections with the Mac rogue Trojans," but didn't specify the raw numbers or the rate of increase in infections.
Companies like Intego, of course, have an interest in touting MacDefender's ubiquity: They sell antivirus software for the Mac.
F-Secure, in fact, launched its first Mac-specific product today.
Symantec, which has one of the world's largest network of malware sensors and "honeypot" systems -- and also sells Mac security software -- said it didn't have "much if anything, in the way of hard data/numbers" on the Mac scareware campaigns.
Bottom line: There's no solid evidence yet on how many Mac users are falling for the con.
Why the Mac? Why now? The question should be, "Why not before this?"
Scareware has hammered Windows users for years, and remains a very popular way for criminals to make money. According to Microsoft's latest security intelligence report, the company's MSRT cleaned millions of scareware-infected Windows PCs last year.
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