A
Don't use any kind of "anti-virus" or "anti-malware" product on a Mac. There is never a need for it, and relying on it for protection makes you more vulnerable to attack, not less.
You installed one or more variants of the "InstallMac" trojan. Take the steps below to disable it.
The criminal behind this attack tries to make the malware hard to remove by varying the names of the files it installs. This procedure works as of now, as far as I know. It may not work in the future. Anyone finding this comment a few days or more after it was posted should look for a more recent discussion, or start a new one.
Back up all data before continuing.
1. Triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination command-C:
~/Library/LaunchAgents
In the Finder, select
Go ▹ Go to Folder...
from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return. A folder named "LaunchAgents" will open.
2. Inside the folder you just opened, there may files with a name of the form
something.download.plist
something.ltvbit.plist
something.update.plist
where something is usually a meaningless string, such as any of the following:
InKeepr
InstallMac
Javeview
Leperdvil
Manroling
Otwexplain
These are examples, not a complete list. The string could be anything. The point is that the same string will appear in the name of three files.
You could have more than one copy of the malware, with different values of something.
Move all such items to the Trash. There may not be any other files in the LaunchAgents folder; in that case, you can delete the folder, but otherwise don't delete it. Other files in the folder are not necessarily malicious (though they could be, if you also installed some other kind of malware.)
Log out or restart the computer. The trojan will now be inactive, but there are a few more components of it that should be cleaned up.
3. Open this folder in the same way as above:
~/Library/Application Support
and move to the Trash any subfolders named with the same something you found in Step 2.
Don't move the Application Support folder or anything else inside it.
4. Open the Applications folder. If there is an item with the same name as in Step 3, or any of the other names listed in Step 2, drag it to the Trash.
If in doubt, press the key combination option-command-4 to arrange the apps by date added. Look at the apps that have been added since you first noticed the problem. If there is one you don't recognize, drag it to the Trash.
Empty the Trash.
If you get an alert that the application is in use, force it to quit.
5. From the Safari menu bar, select
Safari ▹ Preferences... ▹ Extensions
Uninstall all extensions you don't know you need. If in doubt, remove all of them. None is required for normal operation. Do the equivalent in the Chrome and Firefox browsers, if you use either of those.
6. Reset the home page in each of your browsers, if it was changed. In Safari, first load the home page you want, then select
Safari ▹ Preferences... ▹ General
and click
Set to Current Page
B
You may also have installed one or more variants of the "VSearch" ad-injection malware. Follow Apple Support's instructions to remove it.
If you have trouble following those instructions, see below.
Malware is always changing to get around the defenses against it. This procedure works as of now, as far as I know. It may not work in the future. Anyone finding this comment a few days or more after it was posted should look for a more recent discussion, or start a new one.
The VSearch malware tries to hide itself by varying the names of the files it installs. To remove it, you must first identify the naming pattern.
Triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination command-C:
/Library/LaunchDaemons
In the Finder, select
Go ▹ Go to Folder...
from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return.
A folder named "LaunchDaemons" may open. Look inside it for two files with names of the form
com.something.daemon.plist
and
com.something.helper.plist
Here something is a variable string of characters, which can be different in each VSearch infection. So far it has always been an alphanumeric string without punctuation, such as "cloud," "dot," "highway," "submarine," or "trusteddownloads." Sometimes it's a meaningless string such as "e8dec5ae7fc75c28" rather than a word. Sometimes the string is "apple," and then you must be especially careful not to delete the wrong files, because many built-in OS X files have similar names.
You could have more than one copy of the malware, with different values of something.
If you find these files, leave the LaunchDaemons folder open, and open the following folder in the same way:
/Library/LaunchAgents
In this folder, there may be a file named
com.something.agent.plist
where the string something is the same as before.
If you feel confident that you've identified the above files, back up all data, then drag just those three files—nothing else—to the Trash. You may be prompted for your administrator login password. Close the Finder windows and restart the computer.
Don't delete the "LaunchAgents" or "LaunchDaemons" folder or anything else inside either one.
The malware is now permanently inactivated, as long as you never reinstall it. You can stop here if you like, or you can remove two remaining components for the sake of completeness.
Open this folder:
/Library/Application Support
If it has a subfolder named just
something
where something is the same string you saw before, drag that subfolder to the Trash and close the window.
Don't delete the "Application Support" folder or anything else inside it.
Finally, in this folder:
/System/Library/Frameworks
there may be an item named exactly
v.framework
or else an item named
something.framework
Again, something is the same string as before.
This item is actually a folder, though it has a different icon than usual. Drag it to the Trash and close the window.
Don't delete the "Frameworks" folder or anything else inside it.
If you didn't find the files or you're not sure about the identification, post what you found.
If in doubt, or if you have no backups, change nothing at all.
The trouble may have started when you downloaded and ran an application called "MPlayerX." That's the name of a legitimate free movie player, but the name is also used fraudulently to distribute VSearch. If there is an item with that name in the Applications folder, delete it. I don't recommend that you install the genuine "MPlayerX," because it's hosted on the rogue "SourceForge" website and is bundled with other malware.
This trojan is often found on illegal websites that traffic in pirated content such as movies. If you, or anyone else who uses the computer, visit such sites and follow prompts to install software, you can expect more of the same, and worse, to follow. Never install any software that you downloaded from a bittorrent, or that was downloaded by someone else from an unknown source.
In the Security & Privacy pane of System Preferences, select the General tab. The radio button marked Anywhere should not be selected. If it is, click the lock icon to unlock the settings, then select one of the other buttons. After that, don't ignore a warning that you are about to run or install an application from an unknown developer.
Then, still in System Preferences, open the App Store or Software Update pane and check the box marked
Install system data files and security updates (OS X 10.10 or later)
or
Download updates automatically (OS X 10.9 or earlier)
if it's not already checked.
C
"MacKeeper" is a scam with only one useful feature: it deletes itself.
First, back up all data.
Note: These instructions apply to the version of the product that I downloaded and tested in early 2012. I can't be sure that they apply to other versions.
If you have incompletely removed MacKeeper—for example, by dragging the application to the Trash and immediately emptying—then you'll have to reinstall it and start over.
IMPORTANT: "MacKeeper" has what the developer calls an “encryption” feature. In my tests, I didn't try to verify what this feature really does. If you used it to “encrypt” any of your files, “decrypt” them before you uninstall, or (preferably) restore the files from backups made before they were “encrypted.” As the developer is not trustworthy, you should assume that the "decrypted" files are corrupt unless proven otherwise.
In the Finder, select
Go ▹ Applications
from the menu bar, or press the key combination shift-command-A. The "MacKeeper" application is in the folder that opens. Quit it if it's running, then drag it to the Trash. You'll be prompted for your login password. Click the Uninstall MacKeeper button in the dialog that appears. All the other functional components of the software will be deleted. Restart the computer and empty the Trash.
☞ Quit MacKeeper before dragging it to the Trash.
☞ Let MacKeeper delete its other components before you empty the Trash.
☞ Don't try to drag MacKeeper from the Dock or the Launchpad to the Trash.
☞ Don't try to remove MacKeeper while running in safe mode.