I encountered this problem, and after a bit of sleuthing I discovered what probably caused it on my MacBook (13-inch, Aluminum, Late 2008) and how to correct the problem . . .
The key bit of information was a post about this occurring after someone installed Citrix software . . .
https://discussions.apple.com/thread/4778300?tstart=0
Citrix software already was on the MacBook, which I am repairing, and since I never heard of it, I clicked on its Preference Pane in Mac OS X 10.7.5 (Lion) System Preferences, which then caused the Citrix Preference Pane window to appear, at which time the purpose of the software appears to involve some type of file transferring . . .
Around the same time, I downloaded and tried to install the free trial version of Drive Genius 4 (ProSoft), which would not install, since it needs a higher version of Mac OS X than Lion . . .
I also did a Safe Boot via rebooting when the SHIFT key is depressed, which I did based on something I read in yet another post about a SAFE BOOT doing a bit of disk repairing . . .
And based on another post I found, I did the "sudo find / -name ".DS_Store" -depth -exec rm {} \;" command in Terminal, but minus the outer quotation marks. This did something and ran for about 10 to 16 minutes, but after rebooting the problem with Finder continued . . .
https://discussions.apple.com/thread/3193215?start=0&tstart=0
Yet another thing I noticed is that when I tried to do a Restart via the Apple main menu, the "FinderInjectionTool" prevented it, as it did when I tried to do a Shutdown, so instead I just held-down the MacBook power button until the MacBook shutdown, and then I started it in SAFE MODE, at which time I removed the two applications, one of which definitely was the culprit . . .
I am reasonably comfortable that this problem in the scenario I described was caused either (a) by running the Citrix software or (b) by downloading and trying to install Drive Genius 4, where with respect to the latter, I downloaded it from the ProSoft website, not from a third-party website . . .
WHAT I KNOW
(1) Booting in Safe Mode makes it possible to fix a few things . . .
(2) Removing the Citrix software preference pane from System Preferences and deleting the Citrix Preference Pane application from the "Applications" folder was productive . . .
(3) Moving the Drive Genius 4 download from the Mac OS X Desktop to the Trash can was productive . . .
(4) Running the "sudo find / -name ".DS_Store" -depth -exec rm {} \;" command in Terminal did not appear to do anything useful, but it did no harm as far as I can determine . . .
SUMMARY
I think this qualifies as a malware attack, so it's the first one I have encountered on the Mac since the year 2000 when I got my first Mac . . .
Whether this qualifies as being "hacked" is another matter, but so what . . .
I think it qualifies . . .
It took about two hours of research via Google and doing some experiments based on a combination of (a) information found in various posts and (b) what I know about the Mac . . .
The problem is fixed, which is fabulous!
Fabulous! 🙂
P. S. In some respects, I am a bit of an idiot for clicking on stuff without having any idea what it does or might do, but (a) I cloned the MacBook hard drive with SuperDuper! (Shirt Pocket) yesterday, which was before I wandered into experimenting today, and (b) I plan to replace the current MacBook hard drive with a new hard drive or perhaps a SSD drive, so I had a verified recovery plan in place before I started doing today's experiments, hence it's all good, and now I can get the coveted, "I have a Mac and I've been hacked!" tattoo on my
my naughty bits, so to speak . . . 😝