Just because you're paranoid… MacBook edition.

June 23, 2015 5:30 PM

Is somebody remotely controlling my MacBook's trackpad/mouse?

My son's MacBook Pro (13", 2012) sometimes get's 'crazy mouse syndrome', where the pointer starts jumping around, randomly clicking on things, etc. It happens mostly when playing Minecraft or sometimes when he's watching Youtube videos (where it will click on random videos). It doesn't matter whether he has a mouse plugged in or not.
Today, I was playing Besiege (via Steam) and it started up again, and I noticed it didn't seem so random, the mouse was moving and clicking on the fairly small menu area, and trying to click on the 'destroy' button, it basically looked like a person was pranking me.
I got paranoid that somebody was controlling the MacBook remotely and managed to shut off the WiFi (which was a struggle), and BAM, the craziness stops. I turned the WiFi back on and it stayed OK.
So, I wonder if I'm being paranoid or is there some sort of backdoor thingie on his computer, and how do I identify it and get rid of it?
This does not happen all the time, and he says it's gotten better, but it just happened to me 30 minutes ago.

posted by signal to Computers & Internet (23 answers total)

Entirely possible that there's just schmutz on the trackpad. Use a little isopropyl on a cottonball to clean it off.
posted by hollisimo at 5:36 PM on June 23, 2015 [1 favorite]

Also, if you're still worried, you can disable Screen Sharing and Remote Management through System Preferences > Sharing, and untick both of those options.
posted by hollisimo at 5:38 PM on June 23, 2015 [2 favorites]

Are you using a wireless (Bluetooth) mouse? Is it possible that someone else's mouse got paired with your son's computer?
posted by monospace at 5:40 PM on June 23, 2015 [6 favorites]

Could also be a problem with an external wireless mouse.
posted by vogon_poet at 5:40 PM on June 23, 2015

I don't think there's any way this could happen through the WiFi. Wireless mice and trackpads connect through Bluetooth, and you can see what Bluetooth devices are connected by clicking the Bluetooth menu on the top-right of your screen (it's that icon that looks like a kind of runic-styled B).

I've had a MacBook trackpad go in a way that caused it to move around and occasionally click. The erratic movements could definitely result in it getting "stuck" on one part of the screen for a while; this is a pretty common way for trackpads to fail, and IIRC the replacement cost is under $100 and can be done at an Apple Store without sending it out. (But they did take a couple days.)

It's always possible it got paired to some Bluetooth mouse or trackpad but the range on those things is fairly short -- 30 feet, maybe? It's probably not that, especially as someone deliberately trying to prank you would need to be able to monitor your screen as well.
posted by mister pointy at 5:48 PM on June 23, 2015 [1 favorite]

This happened to me occasionally after I spilled a few drops of water on/near the trackpad. I too freaked out before I remembered the spill. It was only a few droplets, so it dried out quickly and there was no lasting damage. So my vote is for liquid/something else stuck underneath. You can take it to the Apple store and they can open it up and clean it up a little in there. If that doesn't fix it, you can just have them replace the trackpad. I had to do that after a slightly more disastrous liquid spill that led to a stuck trackpad, and it only cost about $90 or so.
posted by yasaman at 5:48 PM on June 23, 2015 [4 favorites]

I have a wireless keyboard with an integrated trackpad, and every once in a while if there's a bit too much moisture on my fingers or if a dog hair has floated onto it, it will cause the cursor to jump a few inches away on the screen. The movement can look very natural since it still responds somewhat to my finger movements, but it's displaced because something is there interfering with the touchpad's capacitance.

This doesn't explain 100% of your issues but it could explain some of them. This coupled with the issues with a bluetooth connected external mouse that people above have described could explain everything.
posted by phunniemee at 5:48 PM on June 23, 2015

Response by poster: Bluetooth, Screen Sharing and Remote Management were already off. There is some gunk on the trackpad, but I don't see how that would give the intermittent behavior I observe.
posted by signal at 5:54 PM on June 23, 2015

My trackpad issues were intermittent as well. I think you need to take it to an Apple Store.
posted by mister pointy at 6:15 PM on June 23, 2015

Response by poster: OK, thanks for the answers. Nobody gives any credence to my paranoid fantasy about being remotely controlled?
posted by signal at 6:34 PM on June 23, 2015 [2 favorites]

Like any computer, you can set up a Mac for remote control by an outside party. And on Windows, this functionality has been abused to make so-called remote access Trojan (RAT) malware -- which would be exactly what you're worried about. But I've never heard of software like this targeting OS X. So it's not impossible but pretty unlikely.
posted by vogon_poet at 7:00 PM on June 23, 2015

I had an issue with intermittent trackpad failure on a 2010 MBP that manifested much like this -- intermittent random cursor jumping around. There were also "dead areas" on the trackpad, where touching had no effect. Took it to the Apple Store and $90 / four days later, shiny new trackpad!

I've also noticed that if I get any water (or any other capacitive substance) on the trackpad, as in, say, water on my fingertips after washing my hands but not drying thoroughly, the trackpad will freak out like this. Generally wiping it dry helps; once, I've had to restart to clear the fault.

So I'm thinking the odds are high it's schmutz and/or a failing trackpad. If cleaning it doesn't help and Apple can't find anything wrong with the trackpad, THEN worry about remote control exploits.
posted by Alterscape at 7:08 PM on June 23, 2015 [2 favorites]

This was happening to me for several weeks.
Being the crazy risk taker that I am, I use my Macbook in the kitchen when I'm cooking, to look at recipes, watch videos to entertain myself, etc. Maybe about a month ago I knocked over a glass, breaking it. I quickly grabbed the Macbook to get it away from the spill, but my hands were a bit wet, & I suspected some water had got into the trackpad as the cursor began going bonkers immediately after. No liquid got into it via the spill on the counter.
I tried a few fixes I found on line (running paper around the edges of the trackpad, opening the back & cleaning, etc) but the problem would return hours later, or the next day, or after opening it after a trip to or from one place to another.
I eventually took it to the Apple Store on Saturday to get the trackpad replaced, the Genius ran a few tests & diagnosed it as a software fault. I was a bit dubious about this, but agreed to erase the hard drive. Went home, restored from Time Machine, and voila, it's been 4 days now & everything is fine. Also there's less spinning going on, so that's a bonus.
posted by goshling at 7:21 PM on June 23, 2015

Nobody gives any credence to my paranoid fantasy about being remotely controlled?

If you want to check it out, and you are OK with digging around your system, here are some things to carefully look at:

I would open up Macintosh HD (or whatever the hard drive is called), then open up Library, then open up Application Support. Look for anything there that you didn’t install & didn’t come from Apple...like TeamViewer, LogMeIn, or Join Me. Don’t randomly delete things just because you don’t recognize the name; this is just an exploratory mission.

Next, go back to Library and check for the same things in the LaunchAgents, LaunchDaemons and StartupItems folders.

Again, don’t delete anything just because you don’t recognize it; you could hose your operating system if you delete something the system requires.

I have yet to see any Mac malware in the wild with a remote control backdoor; that doesn’t mean that someone in your household didn’t accidentally install some legit or semi-legit software that can allow remote control.
posted by bcwinters at 7:41 PM on June 23, 2015 [3 favorites]

I had weird trackpad jitteriness a few weeks ago, and simply booting into safe mode one time seems to have fixed the problem for good.

Does the mouse go to other places seemingly deliberately, or was it just that one specific game?
posted by nom de poop at 7:49 PM on June 23, 2015

It certainly *could* be some remote access malware, but a hardware problem with the trackpad could also cause the behaviour you've seen. One way to help narrow down the cause (if you have a mouse you could plug in for him to use instead of the trackpad) is to go to System Preferences > Accessibility > Mouse & Trackpad and check the box for "Ignore built-in trackpad when mouse or wireless trackpad is present". This will totally disable the trackpad as long as he's using the external mouse, so if you continue to see this issue then it's almost certainly a software or malware issue.
posted by russm at 9:24 PM on June 23, 2015 [2 favorites]

(the exact location of that preference is current OS X, in some earlier versions the control panel is called "Universal Access" instead of "Accessibility")
posted by russm at 9:27 PM on June 23, 2015

It's absolutely possible that someone is controlling your machine via the internet. It's really not likely though. I bet the most likely cause is a hardware issue with your trackpad. Two things might make it clear whether or not it's a hardware issue.

1) can you find out of this happens even without internet access? If it happens when your computer can't access the internet, it's pretty much impossible for it to be a remote attacker.

2) you could physically disconnect your MacBook's trackpad, and rely on wired keyboard and mouse for a while. If you didn't experience crazy cursor issues during this time, you could be more confident it's a hardware issue. You'll want to find instructions for replacing the keyboard/trackpad on fixit.com and see what it would take (if it's an older MacBook this will probably be easier than a Unibody MacBook)
posted by reeddavid at 10:15 PM on June 23, 2015

In general moving the mouse to click on things is the least convenient and easiest to notice way to remotely access someone else's computer. If you're running your own software on their computer, you don't need to click; that software can do what you want already. So I think it's probably not something nefarious. Nothing's 100% but odds are it's just a trackpad problem or something. (You don't have any other pointing devices plugged in, right?)
posted by aubilenon at 11:14 PM on June 23, 2015 [2 favorites]

The tiniest drop of water can have an amazing effect on a Macbook trackpad, exactly as you describe.

I've gotten to the point where it just Would. Not. Stop. no matter how I cleaned it. I ended up hitting it with a blow dryer, on low, from a safe distance.
posted by drjimmy11 at 1:11 AM on June 24, 2015

russm's advice about disabling the trackpad when an external mouse is attached saved me from tossing the macbook out the window.

Mine was randomly residing windows, zooming in & out, going into Dashboard (which I never use, don't have it in Dock), creating new folders on the desktop, deleting apps from Dock, bringing up right click context menus, general jiggling about and zooming frantically across the screen.
It'd get worse if my fingers had perspiration on them.

Of course, as soon as I got to the end of my patience & booked the Genius bar appointment, the issue seemed to stop, didn't show itself while the Genius was poking it at for all of 10 seconds (between running hardware dx & software dx), but the software dx he ran resulted in SOFTWARE ERROR in huge letters across the entire screen, so I went along with his wipe & restore plan, so who knows. Maybe it just took 6 weeks & the magic of booking an appt with a Genius for some obscure droplet of water to dry out.

The Genius commented that it was a bit "greasy" - I said, "Yes! I do massage, everything I touch is covered in massage oil, I've been typing on that thing with massage oil on my hands since I bought it in April 2011, I don't think that's the problem."
Since Monday I'm back to typing client notes in the middle of session with oily hands, no problems with the trackpad or anything else.

Conclusion: Go see a a Genius.
posted by goshling at 1:42 AM on June 24, 2015

Thinking about this a bit more, and I think the best evidence in favor of "rule out problems with the trackpad before you worry about malware" is that it is not in the interest of a malware user to taunt you by screwing with your mouse while you're trying to play Beseiged. If your system was compromised by malware, the people controlling it would want to lay low and prevent you from knowing that malware was installed for long enough to get at your juicy financial details, not rub it in your face by tweaking your mouse while you played Beseiged. Now that you saw some irregular behavior you're on the alert, which is exactly what a bad actor would want to avoid, I think. It's theoretically possible that you got compromised by some lulzy troll who just wants to screw with peoples' gaming experiences. This all suggests to me that you've probably just got schmutz on your trackpad and should see about getting it cleaned first, though.
posted by Alterscape at 8:32 AM on June 24, 2015

OK, thanks for the answers. Nobody gives any credence to my paranoid fantasy about being remotely controlled?

If you really want to test this out, remove any possibility of a remote connection by completely isolating your laptop from a network: Put your laptop in a Faraday cage and see if the mouse pointer stops jumping around.

If it doesn't stop after network isolation, take your laptop to an Apple Store for repairs.
posted by a lungful of dragon at 8:34 AM on June 24, 2015