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I always feel like somebody's watching me
December 20, 2013 8:31 AM   Subscribe

For years we've been told that our laptop cameras and webcams are "hardwired" to an LED such that the camera can't be turned on without triggering the light. Yeah, you can see where this is going (the original paper). The exploit works on pre-2008 Macs, though other laptops and webcams could be vulnerable to a similar exploit. The researchers have a kernel extension to prevent this on 2007 / 2008 MacBooks. My preferred solution for the rest of us.
posted by dirigibleman (96 comments total) 16 users marked this as a favorite

 
First validate and hand compile the compiler that you use to build the fix...
posted by sammyo at 8:41 AM on December 20, 2013 [11 favorites]


This reminds me of something I've wondered for a while now, why does Rockwell shower in his underwear?
posted by The 10th Regiment of Foot at 8:41 AM on December 20, 2013 [9 favorites]


Putting tape over the camera is a great solution! Wish I would have thought of that before I spent all that money on disguises.
posted by orme at 8:45 AM on December 20, 2013 [38 favorites]


Anyone who enjoys watching several hours of frowning, muttering, and occasional farting is in for a treat when they hack my camera.
posted by Segundus at 8:49 AM on December 20, 2013 [16 favorites]


I'm always uploading my home and office cams to YouTube 24/7 anyway.
posted by planetesimal at 8:52 AM on December 20, 2013


Hold on, I've just realised I can lay on some puerile sniggering, too.
posted by Segundus at 8:52 AM on December 20, 2013


The easiest way to solve this from the perspective of the laptop manufacturer would be to add a physical cover over the camera. It could be as simple as a piece of plastic that can be pushed one way to cover and the other way to uncover. People who use their laptop cameras a lot would probably just leave it uncovered all the time anyway, but a lot of people never use their camera at all.
posted by burnmp3s at 8:52 AM on December 20, 2013 [5 favorites]


I have another idea! A sliding hardware switch by the camera that covers it when in 'off' position and also switches off the light. I wonder why not one of laptop manufacturers implemented it.
posted by hat_eater at 8:54 AM on December 20, 2013 [3 favorites]


I wonder if a physical cover for the webcam would go against accessibility guidelines.
posted by planetesimal at 8:55 AM on December 20, 2013 [2 favorites]


dammit
posted by hat_eater at 8:55 AM on December 20, 2013


Hold on, I've just realised I can lay on some puerile sniggering, too.

Don't forget the nosepicking.

I have another idea! A sliding hardware switch by the camera that covers it when in 'off' position and also switches off the light. I wonder why not one of laptop manufacturers implemened it.

The sad thing is that my first thought was "Would the NSA allow that?"
posted by Dip Flash at 8:55 AM on December 20, 2013 [1 favorite]


Yeah, I've had a piece of post-it stuck over my laptop camera since the day it came out of the box. Anything else would feel very strange.
posted by elizardbits at 8:55 AM on December 20, 2013 [6 favorites]


Post-it notes. Seriously, just cut to size. Comes off easy too.
posted by 2bucksplus at 8:56 AM on December 20, 2013 [2 favorites]


In typical newspaper style, the information is meted out in scattered style seemingly meant to defy understanding. However, it seems that:

1) web cameras in the past have been either easily configurable or hackable to not turn on the light when filming (nice one, Logitech)

2) the 2008 Macbook had a feature that should have made it impossible to film withut showing the LED.

3) The firmware allowed some sort of override! Bad Apple.

4) Charlie Miller thinks that more recent models are probably susceptible to similar attacks, but it would take considerable resources to find out (hello government intelligence agencies).

So webcams could be recording. Also, what about that microphone in there... Or the one on your cell phone that you carry everywhere?
posted by Llama-Lime at 8:57 AM on December 20, 2013 [1 favorite]


Disabling the camera in "Device Manager" isn't good enough?
posted by notyou at 8:58 AM on December 20, 2013


My wife and I use Post-It notes, too. Now I like to imagine some hacker trying to turn our camera on and being all like "Curses! Foiled again!"
posted by The Card Cheat at 8:59 AM on December 20, 2013 [2 favorites]


Disabling the camera in "Device Manager" isn't good enough?

No software solution is good enough. Software settings can be changed remotely.
posted by hat_eater at 9:01 AM on December 20, 2013 [6 favorites]


burnmp3s: "The easiest way to solve this from the perspective of the laptop manufacturer would be to add a physical cover over the camera. It could be as simple as a piece of plastic that can be pushed one way to cover and the other way to uncover. People who use their laptop cameras a lot would probably just leave it uncovered all the time anyway, but a lot of people never use their camera at all."

My Logitech webcam (external, not built-in,) came with one. Literally a curved piece of black plastic that could be raised or lowered over the lens, or removed completely.
posted by zarq at 9:01 AM on December 20, 2013


Cellphone: Check
Onstar/Other automotive systems: Check
Car License Plates: Check
Email: Check
Web access points: Check
Webcam: Check

Tinfoil: ???
posted by lalochezia at 9:01 AM on December 20, 2013 [5 favorites]


So, until I need it I should just keep all of my personal electronics in a Faraday cage. Or am I jumbling up my physics and the frequencies wireless runs on don't give a fig for the cage?
posted by Slackermagee at 9:04 AM on December 20, 2013


tape over the camera has always been my go to method. i was always baffled at people who said things like "you can't turn on the camera and keep the light off!" because no matter what assurances are given, that just seems to be a weak bit of logic.
posted by nadawi at 9:08 AM on December 20, 2013 [1 favorite]


If people want to see what my face looks like when I masturbate, they need merely ask.
posted by Bunny Ultramod at 9:10 AM on December 20, 2013 [34 favorites]


the frequencies wireless runs on don't give a fig for the cage?

Not if you size the mesh right.
posted by achrise at 9:12 AM on December 20, 2013 [2 favorites]


Any kernel module that can be added, can be overridden.

It's likely the light is controlled by updatable firmware on all laptops. As it happens, the biggest lie about your computer is that it's just one computer. There's something like 7 ARM chips in an iPhone 5 alone. All of these computers need to get their instructions from somewhere, and all of those instructions can be updated. This is one of the reasons why things like secure boot are thoroughly doomed; there's always somewhere else to shove your malware.
posted by effugas at 9:13 AM on December 20, 2013 [2 favorites]


This reminds me of something I've wondered for a while now, why does Rockwell shower in his underwear?

There's nothing wrong with him!
posted by Strange Interlude at 9:13 AM on December 20, 2013 [1 favorite]


3M, if they are smart and want to capitalize on current distrust, should make a sleek black "privacy tape". Shit, just rebrand these and sell them in smaller packs for more money.
posted by 2bucksplus at 9:14 AM on December 20, 2013 [3 favorites]


It's been reasonably common for cameras to specifically include software functions that override the "on" light (mine certainly did, back when I had one, and it was run-of-the-mill Logitech).

The only reason this is noteworthy is they actually had to try hard to override the light, and in the process performed a nifty hack -- overriding the light has been, until fairly recently, a trivial hack.
posted by aramaic at 9:15 AM on December 20, 2013 [1 favorite]


Not a laptop, but the Dell Optiplex All-in-One 9010 comes with a built-in webcam and just the kind of slideable plastic cover for it suggested upthread.

Of course, that does bupkis for the microphone, as do all the post-its and tapes of the world. I'm still not decided about what to do with the microphone, honestly. (And the first thing I did with my laptop when I turned it on for the first time was to disable the camera from the settings, but that's not a solution because of the obvious, and the first thing I did with the Dell AiO was to slide that plastic bit to cover the webcam while being happy that they had thought of it.)
posted by seyirci at 9:15 AM on December 20, 2013


im sure that laptops that include webcams as a feature would never include a cover. That would be tantamount to advertising security flaws.
posted by rebent at 9:15 AM on December 20, 2013


aaaand on lack of preview I see that I am incorrect. Thanks Seyirci :)
posted by rebent at 9:16 AM on December 20, 2013 [1 favorite]


All the microphone is going to hear is me laughing like a drunk donkey. Or shrieking at puppy videos.
posted by elizardbits at 9:19 AM on December 20, 2013 [5 favorites]


rebent: Well, the All-in-One is marketed as a business computer (and in fact it's my work computer), so it was quite probably a requirement to be able to block the camera. Trade secrets and other secrets and all that. Dell markets aggressively to government contractors, too.
posted by seyirci at 9:20 AM on December 20, 2013


Note that the paper only describes "previous generation Apple products including the iMac G5 and early Intel-based iMacs, MacBooks, and MacBook Pros until roughly 2008." It is unclear to me whether more recent models suffer from the same vulnerability. I guess one could run the proof of concept app to check.

I will say I am quite shocked that Apple didn't adopt any of the secure indicators. I had been under the impression that the power to the camera was hardwired to the power to the LED. It's such an obvious and complete solution to the problem.
posted by jedicus at 9:20 AM on December 20, 2013 [2 favorites]


Yeah, when all the spooks or children of spooks I know started taping up their webcams 2 or 3 years ago I thought they were probably on to something.
posted by fontophilic at 9:29 AM on December 20, 2013 [1 favorite]


If people want to see what my face looks like when I masturbate, they need merely ask.

Like anyone is falling for that one again.
posted by cjorgensen at 9:31 AM on December 20, 2013 [5 favorites]


One valid reason I can think of for wanting to be able to turn the camera on without turning on the LED light is if my laptop gets stolen and I want to be able to surreptitiously take pictures of the person using my laptop for purposes of identifying the thief.
posted by gyc at 9:32 AM on December 20, 2013 [2 favorites]


If people want to see what my face looks like when I masturbate, they need merely ask.

Bluff called, yo.
posted by griphus at 9:33 AM on December 20, 2013 [13 favorites]


3M, if they are smart and want to capitalize on current distrust, should make a sleek black "privacy tape".

The EFF has had these for a while.
posted by George_Spiggott at 9:42 AM on December 20, 2013


>>If people want to see what my face looks like when I masturbate, they need merely ask.

Bluff called, yo.


I feel like this calls for a triple-dog dare.
posted by slkinsey at 9:44 AM on December 20, 2013 [5 favorites]


Use electrical tape with a little square of regular paper, to protect the lens of the computer's camera if you should want to use the camera ever. You can uninstall the microphone in your computer as well, and use a headset if you want to Skype. I bought this computer in 2007, and put the tape on before I turned it on. Three times in the first week of use, sites popped up at random telling me I was having problems with my web cam, and would I like some help fixing it? There are phone covers on the market, military type, with lens covers for the standard phone types. I don't have enough money to really interest anyone, nor any other "assets."

I also covered the web cams in my classroom computers, because I felt that they are so hackable they constituted a FERPA violation with regards to my students' privacy, not only my own. There is no more vulnerable population of computer users than American students as districts "carefully monitor" all computer use. Then district employees can set up dates with cute, vulnerable students, by knowing private data that compromises their ability to say no. They can turn students over to the police if they violate acceptable use policies, and set them up for abuse by crooked law enforcers.
posted by Oyéah at 9:44 AM on December 20, 2013 [1 favorite]


All the microphone is going to hear is me laughing like a drunk donkey.

This is elizardbits AICMFP.
posted by ROU_Xenophobe at 9:46 AM on December 20, 2013 [5 favorites]


My Asus laptop's integrated webcam has a sliding cover. Is that really so rare?
posted by maudlin at 9:47 AM on December 20, 2013


If people want to see what my face looks like when I masturbate, they need merely ask...

...their therapist for more and stronger antipsychotics.
posted by The 10th Regiment of Foot at 9:48 AM on December 20, 2013 [4 favorites]


Why do people ever believe that this kind of thing can't happen? Unless the iris inside the camera is physically connected to a little sliding red/green strip of material inside a cutout in the metal next to the lens...it's gonna be hackable folks.

Next, people will be shocked (shocked!) that their cell phones can be turned on when they're off, listen when they're not lit up, and transmit their location even when not in use.
posted by trackofalljades at 9:49 AM on December 20, 2013


All of this hackalicious stuff didn't start last week, the inventors of the internet made it a yummy swiss cheese of back doors, loops, peekholes, all automatically monitored by big bro, in many it is for surveillance, with considerable side use by other interests who profit highly by all of the features available. It is fun for us, and we are like a flight of starlings, safe seeming in high numbers, but not really. There is no bluffing this system unless you are a very capable author.
posted by Oyéah at 9:49 AM on December 20, 2013 [1 favorite]


Is that really so rare?

Yes, because you have to make the lid thicker to accommodate it and still get the same focal length in the camera. Okay in luggables, not so hot in ultrathin n' lights.
posted by George_Spiggott at 9:50 AM on December 20, 2013


Can you see me now?
posted by It's Raining Florence Henderson at 9:50 AM on December 20, 2013


Yes, and you have coffee foam on your nose again.
posted by elizardbits at 9:51 AM on December 20, 2013 [3 favorites]


Yes, because you have to make the lid thicker to accommodate it and still get the same focal length in the camera.

So THAT'S why this thing is such a fucking foot locker. And it's a really awful camera, too.
posted by maudlin at 9:52 AM on December 20, 2013


why does Rockwell shower in his underwear?

He thinks someone is watching him.
posted by Hoopo at 9:52 AM on December 20, 2013 [17 favorites]


"Next, people will be shocked (shocked!) that their cell phones can be turned on when they're off, listen when they're not lit up, and transmit their location even when not in use."

When I bought my "smart phone" I didn't cover the camera the first day. The phone woke me up in the middle of the night asking for a picture to put on my email. I got up and cut some tape, put it on and went back to sleep, next day I turned off all the bells and whistles, except for one to know about incoming texts.
posted by Oyéah at 9:53 AM on December 20, 2013 [1 favorite]


Who is Rockwell? I have never seen pictures of the wet tightey whiteys.
posted by Oyéah at 9:54 AM on December 20, 2013


It's already too late. In another year or two they'll be able to hack the trackpad such that they can tap your nervous system through your fingertips and read the visual data from your optic nerve. Why do you think screens are all reflective now even though nobody wants that? They've been preparing us for this for a while.
posted by George_Spiggott at 9:56 AM on December 20, 2013 [2 favorites]


Anyone who enjoys watching several hours of frowning, muttering, and occasional farting is in for a treat when they hack my camera.

I used to belong to a webcam community years ago, after being pestered by friends to join. I always told them "I'm not interesting enough for that." But I joined to shut them up. Who the hell wants to watch some woman read the internet for work? I couldn't imagine.

Then I got email from a dude. "Did you know that you kind of stick your tongue out when you're concentrating really hard? It's very cute!" A few days later, same dude: "Your tits are HUGE! Are they real?" And I dropped out of that community right away. There's a little band-aid over my webcam these days.

As for the microphone? Well, if they want to hear the pitbull barking at every passing squirrel, more power to 'em.
posted by MissySedai at 9:58 AM on December 20, 2013


Are the squirrels real?
posted by It's Raining Florence Henderson at 10:00 AM on December 20, 2013 [5 favorites]


“Apple went to some amount of effort to make sure that the LED would turn on whenever the camera was taking images,” Checkoway says. The 2008-era Apple products they studied had a “hardware interlock” between the camera and the light to ensure that the camera couldn’t turn on without alerting its owner.

Obviously they went to very little effort. If the interlock that prevents use without the LED on is controlled by a microcontroller in the camera module then it's not a "hardware interlock".
I'm an EE and have designed a few small camera modules like this and a true hardware interlock is really quite simple to implement - the camera sensor reset signal is derived from the current through the LED. No LED current means no camera operation.
posted by rocket88 at 10:03 AM on December 20, 2013 [9 favorites]


The squirrels may be in trees falling in a forest that no one is watching, except for the bulldog, so it is an ancient philosophical question unresolved, as to the existence of said squirrels.
posted by Oyéah at 10:06 AM on December 20, 2013


That's more or less what I was thinking, rocket88. There's no reason a plain circuit has to be hackable, no matter what it's attached to. Modern refrigerators have computers in them but I'd bet money you couldn't hack one to make the light go on.
posted by George_Spiggott at 10:18 AM on December 20, 2013


You'd be willing to bet money that refrigerator engineers are less lazy than Apple engineers? I wouldn't. Always bet on laziness.
posted by It's Raining Florence Henderson at 10:21 AM on December 20, 2013


It's not laziness, it's the fact that there's almost certainly nothing but a simple wire connecting the bulb to the door switch and another one to complete the circuit to the main power supply and not a damn thing you can do in the refrigerator logic to influence whether current passes over either of them.
posted by George_Spiggott at 10:24 AM on December 20, 2013 [2 favorites]


I bet the computer knows if the door is open. Probably with alerts. That only happens if that door switch is wired to the computer circuits. If that circuit already exists, I'm just adding the bulb to it. Just guessing, as my refrigerator predates electricity by several centuries.
posted by It's Raining Florence Henderson at 10:28 AM on December 20, 2013


If somebody taps my webcam they'll just see me absentmindedly picking my nose

Every time I think I've broken the habit I'll catch myself cleaning house

"Somebody's Watching Me" became a Top 10 pop hit in both the US and UK, and a #1 R&B hit. Follow-up singles underperformed, however, with single "Obscene Phone Caller" being Rockwell's only other Top 40 single.

I'm guessing his next single would have been "Restraining Order" if his career had taken off
posted by Ray Walston, Luck Dragon at 10:29 AM on December 20, 2013 [3 favorites]


I taped a small mirror over my webcam. That way if somebody taps into it, all they'll see is themselves picking their own nose.
posted by It's Raining Florence Henderson at 10:31 AM on December 20, 2013 [11 favorites]


Sure, but the AC current for the light bulb won't pass through any logic circuitry and the switch is still a mechanical one. The fridge can know the door is open and still not be able to affect whether current flows to the bulb.
posted by George_Spiggott at 10:31 AM on December 20, 2013


I'm an EE and have designed a few small camera modules like this and a true hardware interlock is really quite simple to implement - the camera sensor reset signal is derived from the current through the LED. No LED current means no camera operation.

If you look at page 3 and 4 of the original paper, I think that's the case with the iSight camera as well. If I am understanding this right (I might not be), the issue is that you can use the USB chip to reprogram the image sensor chip to ignore STANDBY and just turn on anyway, which means you can keep STANDBY asserted all the time so that the indicator light is off.

More worrying is that the firmware for the EZ-USB chip is loaded from the host, can be reloaded at any time, the package doesn't have to be cryptographically signed, and you can do it from userspace.

This might be, I suspect, the case with many other peripherals.
posted by tracert at 10:39 AM on December 20, 2013 [2 favorites]


The easiest way to solve this from the perspective of the laptop manufacturer would be to add a physical cover over the camera.

Like this Kinect eyepatch for the Xbone.
posted by MartinWisse at 10:47 AM on December 20, 2013


Since they don't want to take the thickness hit by putting a sliding cover over the lens, there's another possibility. Pretty sure there's going to be an air gap between the lens and the sensor. Even if it's a fraction of a millimeter that's still enough to interpose a sliding shutter between them, which you could operate with a slider on the bezel.
posted by George_Spiggott at 10:50 AM on December 20, 2013


tracert, STANDBY is overridable while RESET (which rocket88 was referring to) is not.

On page 9, see their suggested hardware solution #2:
The LED driver circuit can be connected to the #RESET pin and a GPIO pin on the microcontroller. The microcontroller would hold the image sensor in reset whenever it was not capturing images. Compared to the power connection for CMOS sensor, holding the entire sensor-on-a-chip in reset means that before images could be captured, the sensor would need to be reconfigured. Reconfiguring typically means sending a few dozen bytes over an I2C or SPI bus. This introduces a slight delay.
So, they mention this, but decided it was a sub-optimal solution due to added delay.
posted by caaaaaam at 10:57 AM on December 20, 2013 [2 favorites]


Why can't there be a mechanical switch that physically disconnects the camera and microphone?
posted by dirigibleman at 11:10 AM on December 20, 2013 [2 favorites]


I did the electrical tape thing for a while until I bought myself an ALFA Networks external USB wireless adapter and the clip-on holder to go with it -- just clip it on over the camera lens and you're good to go, and no sticky tape goo to deal with either!
posted by Fuzzypumper at 11:24 AM on December 20, 2013


What I would like is a hack that until deactivated, replaces camera image with this. AND an electric tape for those dedicated enough to defeat the hack.
posted by hat_eater at 11:33 AM on December 20, 2013 [1 favorite]


Okay, I understand now, didn't see that. Thanks caaaaaam.
posted by tracert at 11:40 AM on December 20, 2013


This yt is elizardbits AICMFP.

I now have a new perfect video for cheering up my children if they are in bad moods. Thank you.
posted by davejay at 11:43 AM on December 20, 2013


Bandaid. Perfect web cam cover.
posted by pearlybob at 11:47 AM on December 20, 2013


Just thinking out loud, well sorta... but couldn't you de-activate the microphone just by buying a cheap/broken pair of headphones, cutting the wire, and plugging it into the mic jack?
posted by Blue_Villain at 11:52 AM on December 20, 2013 [1 favorite]


I'm pretty sure that the audio cutout in the mini jacks is handled in software now, at least in Macs. There's still some kind of detection in there but all it does is inform a controller that something is or isn't plugged in there, and the system decides to switch inputs/outputs, or not. You can tell because there's often a lag now when things switch over, which wouldn't happen if it were purely mechanical switching.
posted by George_Spiggott at 11:58 AM on December 20, 2013


I assure you, hacking my camera is its own punishment.
posted by Legomancer at 12:15 PM on December 20, 2013 [9 favorites]


This reminds me of something I've wondered for a while now, why does Rockwell shower in his underwear?
... is this a trick question?
posted by Flunkie at 12:16 PM on December 20, 2013


Any dorks who want to stare at my slack-jawed web surfing face deserve what they see.
posted by aught at 12:46 PM on December 20, 2013


This yt is elizardbits AICMFP.

Aiee. Francis Bacon, animated.
posted by aught at 12:50 PM on December 20, 2013


Why electrical tape? I used painter's tape, because it seems less likely to damage the camera (and, more honestly, because it was in arm's reach).
posted by The corpse in the library at 1:05 PM on December 20, 2013


So, they mention this, but decided it was a sub-optimal solution due to added delay.

I haven't read the datasheet, but I'll wager the time required to reset and reconfig the sensor is miniscule compared to the time required for the software driver to load and activate the camera.

Not saying it's intentional, but a good backdoor is indistinguishable from a bad design.
posted by RobotVoodooPower at 1:30 PM on December 20, 2013


Black electrical is almost invisible on a black computer case.
posted by sammyo at 1:40 PM on December 20, 2013 [1 favorite]


You can also buy sheets of various-sized black circles to cover webcams and LEDs and lighted logos and other obnoxious vectors on your electronics.
posted by planetesimal at 1:55 PM on December 20, 2013


You can also buy sheets of various-sized black circles to cover webcams and LEDs and lighted logos and other obnoxious vectors on your electronics.

I got them for use with my cable box, but the area to cover was too small. This is very much YMMV for laptops and desktops.
posted by ZeusHumms at 2:03 PM on December 20, 2013


You can also use stick-on googly eyes.
posted by elizardbits at 3:37 PM on December 20, 2013 [12 favorites]


When I had an interest in network security around 2008 due to a pair of persistent internet stalkers who kept hacking into my various computers, I got into the habit of covering the webcam with duct tape. As someone on the internet said (on the Cracked.com forums; don't ask), "They will only see black. They can stare into the darkness of my soul, as interpreted by my webcam."

Unfortunately, the stalkers wore me down and I sort of lost interest/became less paranoid and I forgot about smartphones...

Maybe it's learned helplessness, but I'm just waiting for technology to advance enough that a persistent stalker/hacker can intercept my actual brainwaves. I don't understand why I'm so fascinating to complete strangers.
posted by quiet earth at 3:48 PM on December 20, 2013 [2 favorites]


I don't understand why I'm so fascinating to complete strangers.

That's just the NSA craving to know for sure if everyone else is equally perverted.
posted by Twang at 10:36 PM on December 20, 2013


So what I'm imagining is a clip on, slimline, usb powered device that both obscures the camera and plays something like the talking stain babble constantly through a tiny piezo speaker directly into the microphone.

If you don't ever want to use your cam/mic look for a teardown video for your laptop. You should be able to unscrew or pry off the bezel portion of your display fairly easily and then just cut the wires. Just be sure to follow the wires directly from the webcam/mic unit because the wifi antennae are often located in the same area. If you want a simple hardware solution and are crafty you could even solder in a mini slide switch and be certain that when it's off there's nothing getting in from that sucker.
posted by mcrandello at 4:16 AM on December 21, 2013


I keep my laptop camera covered with a very classy torn-off corner of a yellow post-it to deter the hordes of hackers who are no doubt dying to watch a woman with hair like a red-headed Polish chicken sit at the computer in a ratty purple t-shirt with no bra, biting the dead skin off her lips and digging in her nose with q-tips.

You know you want me.
posted by Serene Empress Dork at 6:08 AM on December 21, 2013 [4 favorites]


You can secure your camera with tape and CCD-reset mods and whatnot all you like, but unless the OS prevents user-space programs from performing firmware updates, malware can still do this:
The same technique that allows us to disable the LED, namely reprogramming the firmware that runs on the iSight, enables a virtual machine escape whereby malware running inside a virtual machine reprograms the camera to act as a USB Human Interface Device (HID) keyboard which executes code in the host operating system.
posted by flabdablet at 10:15 AM on December 21, 2013


We need actual hardware lights that show when either the camera and the microphone receive power, not sure if that involves modifying drivers in the microphone's case. Also, activists, journalists, etc. should get their machine examined for hardware backdoors since the NSA takes machines in shipping and modifies them.
posted by jeffburdges at 1:44 AM on January 15


The iSight designers pretty clearly thought that their indicator light was an actual hardware light, jeffburdges; the LED is wired to the sensor's STANDBY input in such a way that for the LED to be off, STANDBY must be in a state that disables the sensor.

It's just kind of unfortunate that (a) the sensor can actually be configured to ignore its STANDBY input completely (WTF?) and (b) the camera's USB management microcontroller can easily be loaded with firmware capable of configuring the sensor that way and/or making the iSight behave as a non-camera USB device like a keyboard.
posted by flabdablet at 3:27 AM on January 15


We've no idea if an iSight designer built this flaw into the system intentionally or not.
posted by jeffburdges at 7:41 AM on January 15


Phil Zimmerman Launching Secure "Blackphone"
Ain't too happy about all the American involvement though.
posted by jeffburdges at 5:27 AM on January 16


We've no idea if an iSight designer built this flaw into the system intentionally or not.

Having spent many years working in embedded systems design, my best guess is "not." The feature that disables STANDBY is just a bit that software can set in an internal Reset register, and I would not be at all surprised to find that the engineer responsible for designing the circuitry, and whose decision it was to wire the indicator LED directly to STANDBY, was simply unaware of it.

I can think of no reasonable use case for the existence of such a bit; it's just not something I would expect to find in a chip design. And although that doesn't mean that no such use case exists, it is pretty good grounds to believe that the ability to disable STANDBY from software would come as a surprise to a hardware designer, most of whom are not hugely interested in poking around in obscure corners of the programming sections of their parts data sheets.
posted by flabdablet at 7:44 PM on January 16


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