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MacDefender variants slip past security software

Posted on June 3rd, 2011 at 7:27 AM EDT

More and more reports of new variants of MacProtector, including one now called MacShield, are circulating the internet.  Some of them appear to have been modified just enough to be able to slip past some anti-virus (AV) software.  Although AV software is constantly being updated to catch these new variants, it’s a game of catch-up.

It is important for Mac users to do two things.  First is to be vigilant.  If you get alerts about viruses, don’t panic.  That’s just what these hackers want you to do.  Do not run the installer, if it is downloaded, and if it runs, don’t click the Install button.  As long as you don’t do that, you’re not infected.

Second, if it slipped past AV software, submit the installer to AV vendors so they can more quickly update their definitions.  I highly recommend submitting to the ClamAV project, which is a volunteer project and thus needs everyone’s assistance.  Make sure to include the text “macosx” (no spaces) in the description so that the Mac folks can find those submissions among the floods of Windows malware that get submitted every day.

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Apple releases security update for MacDefender

Posted on May 31st, 2011 at 7:22 PM EDT

Apple released Security Update 2011-003 today, addressing the MacDefender issue.  According to Apple’s documentation on this update, there are three basic additions to assist in dealing with the MacDefender outbreak.  Before reading further, it may be worthwhile to read my Mac Virus Guide, to understand some of the fundamental ideas involved, and Apple’s own document on quarantine.

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MacGuard details

Posted on May 26th, 2011 at 10:32 PM EDT

I managed to get my hands on a copy of MacGuard this evening, and ran it through some tests to try to clarify some of the rumors floating around.  The good news is that, in all, this is just another boring old variant in the MacDefender malware line.  The same old removal instructions still apply, and the application itself does not appear to have developed any new features.  However, when it comes to the installation, there are some notable differences!
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Yet another MacDefender variant: MacGuard

Posted on May 25th, 2011 at 7:34 PM EDT

Another new trojan has appeared in the MacDefender/MacSecurity/MacProtector line.  This time it’s called MacGuard.  From the initial reports, it does not sound like it is significantly different in most respects from the earlier versions.  However, there is one notable difference: it no longer requires an administrative password to install.  I am unclear on this point exactly why…  some sites report that it is installed in the user Applications folder rather than the global one, while others give uninstall instructions that refer to the main Applications folder.  I will report more as I learn more, but for now it appears that the same old MacProtector removal instructions will work, with minor modifications.  First, and obviously, you need to look for the name MacGuard in addition to the other three when removing.  Second, look in both the main Applications folder and the one in your user folder and remove MacGuard from wherever it is.

If anyone has additional information, please let me know, and if anyone finds a live link to the malware, please let me know so I can get a copy of it.

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Identifying and removing MacDefender trojans

Posted on May 7th, 2011 at 2:08 PM EDT

[Edited Thursday, May 26, 9:20 PM]

A lot of people are being affected by MacDefender, or one of the variants of MacDefender (MacSecurity, MacProtector and MacGuard, at this time, possibly more in the future).  As a result, I’m getting a lot of questions from people about how to tell if they’re infected, how to get rid of the trojan and what else they need to worry about.  Hopefully, I will answer all those questions and more here.  For those unfamiliar with these trojans, see my previous MacDefender news posts.
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