7 ms·

I would be more concerned about the microphone. I can easily cover the camera with tape. Also, random pictures of me programming or reading HN are probably less

by justin 13y ago

I would be more concerned about the microphone. I can easily cover the camera with tape. Also, random pictures of me programming or reading HN are probably less damaging audio recordings of conversations I might be having.

hrktb 13y ago
Same here. Even nude photos would be embarrassing, but audio recordings could have effects far worse than some prude shame. Especially since there is no LED to signal the microphone is active, it doesn't need to point anywhere. If it could be activated while the laptop is closed (force wake up a part of the OS for just a few minutes here and there for instance) it would be a really tough problem.
- dunham 13y ago
  Maybe unload/delete the kernel module? (This is how I used to silence the pcspkr beep on Linux.)
  - sirkneeland 13y ago
    But how do we do that on the more and more locked-down computing appliances consumers gravitate towards? One does not simply unload/delete kernel module on an iPad...
    - ancarda 13y ago
      Recent versions of iOS ask for permission to use the microphone.
      - codygman 13y ago
        What if in the case of a "lawful intercept" iOS does not ask for permission?
        sigkill 13y ago
        The beauty of your comment is that just a little over half a year ago you'd be considered a complete conspiracy nut and a paranoid tinfoil hatter but today there's no one even saying anything against you.
  - lawnchair_larry 13y ago
    No, an attacker can just reload it. The hardware is still there, waiting for a driver to control it.
greglindahl 13y ago
I use a cut-out piece of postit note for the camera, and a small piece of etape for the microphones -- seems stable, and both are pretty easy to take off without leaving too much spooge behind.
- superuser2 13y ago
  Does tape actually provide enough impedance to prevent surveillance through your microphones? Seems like all an attacker would have to do is amplify (and possibly filter) the audio a bit.
  - greglindahl 13y ago
    I turned up the mic all the way, did a skype test call. I could hear myself if I shouted (input level=0). If I talked at a normal volume level, it was audible (and the input level showed as 2/15. I might try a couple of layers of tape... EDIT: Yeah, 2nd layer of tape = 0 input level even if I shout really, really loudly. You can't imagine how much my coworkers are enjoying this experimentation!
    - pasbesoin 13y ago
      I wondered about tape along with a suitable sound-dampening material, so this "seat-of-the-pants" experiment is of interest to me. I'd want something more certain for a higher security situation, but this might do me for some "casual" use cases.
    - superuser2 13y ago
      Skype has a noise gate - any play on the microphone below a certain level is cut off. Someone with direct access to your microphone can listen without the noise gate and might still hear.
- cinquemb 13y ago
  What about internal microphones on MB's? osascript -e 'set volume input volume 0' doesn't really produce the expected result…
StringyBob 13y ago
My current Thinkpad has a physical switch to disable radios. I'd like to have a physical 'privacy' switch that cut the power to internal microphones and cameras. To be security aware, this has to be an auditable hardware power switch, and not just an interrupt/driver/bios combination that could be bypassed. It's also prefereable for security to have a an off-by-default switch, than an activity light you might not notice...
- smsm42 13y ago
  Great idea. Must be a physical switch that just cuts all physical links between the camera/microphone and the rest of the system, so that no reprogramming is possible. Unfortunately, little chance to see it in Apple products, as such switch would probably not look "slick" and would probably be considered "confusing for the user" and as such not suitable for implementing.
  - sneak 13y ago
    > Unfortunately, little chance to see it in Apple products, as such switch would probably not look "slick" and would probably be considered "confusing for the user" and as such not suitable for implementing. That was my first thought, but then I realized the absolutely ridiculous extent to which Apple goes to build secure devices, and how "slick" the mute switch is on iPhones and iPads. I wouldn't bet against it.
- fzltrp 13y ago
  That's unfortunately the exception rather than the norm. I have seen laptops with switches for WiFi, and camera obturators, but manufacturers hardly think about these things. It's obviously not an Apple problem only, but it certainly hinders usability to have physical switches. Yet, I really wished they'd make that standard for all media peripheral (and not just on PC, but any device coming with these features). That would however be easily considered as an admission of failure to provide a secure software environment to their customers, and they might not like that aspect of it.
  - userbinator 13y ago
philip1209 13y ago
Some hardening guides suggest having the camera and microphone removed by an apple tech. I'm considering having this done on my next laptop - I just don't use them that often.
- bigiain 13y ago
  That's one big advantage of my old FireWire iSight camera – if the FireWire cable isn't plugged in, you _know_ it's not taking pictures. (And now I half expect to read a new Snowden paper tomorrow detailing how the NSA coerced Apple into fitting batteries and flash storage into webcams so they could be instructed to covertly record video while not plugged in and upload it automatically later…)
11001 13y ago
Not to mention microphone can work as a key logger http://rakesh.agrawal-family.com/papers/ssp04kba.pdf http://rakesh.agrawal-family.com/papers/ssp04kba.pdf
rcthompson 13y ago
Also note that a speaker can be used as microphones as well. (In physics terms they are the same device, which can convert sound to electricity or vice versa.) With modern sound cards having reprogrammable inputs and outputs, I wouldn't be surprised if even a laptop with no microphone installed could record audio. (My friend once had to record herself for a foreign language homework, but her microphone broke. I instructed her to plug her headphones into the microphone jack and ust them instead. It worked, but she had to talk loudly to make them work.)
XorNot 13y ago
The RSA acoustic key recovery hack is particularly terrifying in this instance. Turning on the microphone on the computer can furnish an attacker with everything they need to recover encryption keys stored on the computer.

by justin 13y ago

hrktb 13y ago

Same here. Even nude photos would be embarrassing, but audio recordings could have effects far worse than some prude shame. Especially since there is no LED to signal the microphone is active, it doesn't need to point anywhere. If it could be activated while the laptop is closed (force wake up a part of the OS for just a few minutes here and there for instance) it would be a really tough problem.

dunham 13y ago
Maybe unload/delete the kernel module? (This is how I used to silence the pcspkr beep on Linux.)
- sirkneeland 13y ago
  But how do we do that on the more and more locked-down computing appliances consumers gravitate towards? One does not simply unload/delete kernel module on an iPad...
  - ancarda 13y ago
    Recent versions of iOS ask for permission to use the microphone.
    - codygman 13y ago
      What if in the case of a "lawful intercept" iOS does not ask for permission?
      - sigkill 13y ago
        The beauty of your comment is that just a little over half a year ago you'd be considered a complete conspiracy nut and a paranoid tinfoil hatter but today there's no one even saying anything against you.
- lawnchair_larry 13y ago
  No, an attacker can just reload it. The hardware is still there, waiting for a driver to control it.

greglindahl 13y ago

I use a cut-out piece of postit note for the camera, and a small piece of etape for the microphones -- seems stable, and both are pretty easy to take off without leaving too much spooge behind.

superuser2 13y ago
Does tape actually provide enough impedance to prevent surveillance through your microphones? Seems like all an attacker would have to do is amplify (and possibly filter) the audio a bit.
- greglindahl 13y ago
  I turned up the mic all the way, did a skype test call. I could hear myself if I shouted (input level=0). If I talked at a normal volume level, it was audible (and the input level showed as 2/15. I might try a couple of layers of tape... EDIT: Yeah, 2nd layer of tape = 0 input level even if I shout really, really loudly. You can't imagine how much my coworkers are enjoying this experimentation!
  - pasbesoin 13y ago
    I wondered about tape along with a suitable sound-dampening material, so this "seat-of-the-pants" experiment is of interest to me. I'd want something more certain for a higher security situation, but this might do me for some "casual" use cases.
  - superuser2 13y ago
    Skype has a noise gate - any play on the microphone below a certain level is cut off. Someone with direct access to your microphone can listen without the noise gate and might still hear.
cinquemb 13y ago
What about internal microphones on MB's? osascript -e 'set volume input volume 0' doesn't really produce the expected result…

StringyBob 13y ago

My current Thinkpad has a physical switch to disable radios. I'd like to have a physical 'privacy' switch that cut the power to internal microphones and cameras. To be security aware, this has to be an auditable hardware power switch, and not just an interrupt/driver/bios combination that could be bypassed. It's also prefereable for security to have a an off-by-default switch, than an activity light you might not notice...

smsm42 13y ago
Great idea. Must be a physical switch that just cuts all physical links between the camera/microphone and the rest of the system, so that no reprogramming is possible. Unfortunately, little chance to see it in Apple products, as such switch would probably not look "slick" and would probably be considered "confusing for the user" and as such not suitable for implementing.
- sneak 13y ago
  > Unfortunately, little chance to see it in Apple products, as such switch would probably not look "slick" and would probably be considered "confusing for the user" and as such not suitable for implementing. That was my first thought, but then I realized the absolutely ridiculous extent to which Apple goes to build secure devices, and how "slick" the mute switch is on iPhones and iPads. I wouldn't bet against it.
fzltrp 13y ago
That's unfortunately the exception rather than the norm. I have seen laptops with switches for WiFi, and camera obturators, but manufacturers hardly think about these things. It's obviously not an Apple problem only, but it certainly hinders usability to have physical switches. Yet, I really wished they'd make that standard for all media peripheral (and not just on PC, but any device coming with these features). That would however be easily considered as an admission of failure to provide a secure software environment to their customers, and they might not like that aspect of it.
- userbinator 13y ago

philip1209 13y ago

Some hardening guides suggest having the camera and microphone removed by an apple tech. I'm considering having this done on my next laptop - I just don't use them that often.

bigiain 13y ago
That's one big advantage of my old FireWire iSight camera – if the FireWire cable isn't plugged in, you _know_ it's not taking pictures. (And now I half expect to read a new Snowden paper tomorrow detailing how the NSA coerced Apple into fitting batteries and flash storage into webcams so they could be instructed to covertly record video while not plugged in and upload it automatically later…)

11001 13y ago

Not to mention microphone can work as a key logger http://rakesh.agrawal-family.com/papers/ssp04kba.pdf http://rakesh.agrawal-family.com/papers/ssp04kba.pdf

rcthompson 13y ago

Also note that a speaker can be used as microphones as well. (In physics terms they are the same device, which can convert sound to electricity or vice versa.) With modern sound cards having reprogrammable inputs and outputs, I wouldn't be surprised if even a laptop with no microphone installed could record audio. (My friend once had to record herself for a foreign language homework, but her microphone broke. I instructed her to plug her headphones into the microphone jack and ust them instead. It worked, but she had to talk loudly to make them work.)

XorNot 13y ago

The RSA acoustic key recovery hack is particularly terrifying in this instance. Turning on the microphone on the computer can furnish an attacker with everything they need to recover encryption keys stored on the computer.