14
votes
Accepted
Can a speaker be used as a microphone?
One simple experiment you can run is to plug your headphones into a microphone input and speak into them.
Fundamentally, both emitting sound and capturing sound is about dealing with vibrations in ...
- 3,651
12
votes
How to find all the microphones in a room?
This is very broad without a context. If you simply define a microphone as a device able to record sounds, it will be very hard, because microphones can use various technologies, and you will only be ...
- 26.4k
10
votes
Accepted
How practical is a laser microphone and how to protect against it?
Laser Microphones like any other eavesdropping equipment has pros and cons.
Pros
Can be invisible if using infra-red (IR) beam
Will not be detected with typical radio frequency (RF) finders
Can be ...
- 737
9
votes
How sensitive are acoustic side-channels to compression with a narrowband codec?
According to Wikipedia:
"... G.711 passes audio signals in the range of 300–3400 Hz and
samples them at the rate of 8,000"
Nyquist criteria limits the top frequency to be less than half ...
- 8,118
8
votes
How to make sure that no one is watching you through webcam?
If, despite the implausibility of it, you are worried that the FBI has hacked your camera, then I'm afraid there won't be much you can do to gain back control of your camera. Therefore I can only ...
- 31k
6
votes
Mitigating vulnerabilities in audio libraries that cause physical damage
However, nothing is being done about it at this repo which I think is very irresponsible.
Because the "issue" that you're reporting is essentially "users can change the audio volume&...
- 9,267
5
votes
How practical is a laser microphone and how to protect against it?
AS A USER OF THIS TECHNOLOGY (no, LeRoy Theremin did not use this since lasers were not developed until Theodore Maiman made the first laser operate on 16 May 1960 at the Hughes Research Laboratory in ...
- 75
5
votes
Accepted
Virus using input from victims mic to generate encryption keys
If you use some "natural" sound, you have lots of redudancy in it and this reduces the key strength (this may or may not be critical to your application).
Because you cannot reproduce your sound key,...
- 1,698
5
votes
Accepted
Do wireless (2.4 ghz) headphones use encryption?
Bluetooth MAY be encrypted. There are unencrypted modes of both classic bluetooth and BLE which would expose one's audio streams. Let us also not forget that custom BLE profiles may be used however ...
- 2,017
4
votes
Accepted
32-bit Radio Voice Encryption, is it really that secure? If so, how?
I agree with your analysis of the reasons why police departments and other agencies would use "weak" encryption products with their radios: simply because as of the current day encryption crackers are ...
- 1,240
4
votes
I have a very bizarre malware that I cannot seem to get rid of
Your observations aren't plausible from a technical perspective.
Your malware spreads via audio files. Malware can't be arbitrarily "attached" to a file. Rather, a malicious sound file would work by ...
- 44.7k
4
votes
How practical is a laser microphone and how to protect against it?
I am not as experienced as ScottS in the use of this apparatus, but I understand the basic concept of it.
I think that ScottS answers your first question better than I can. As long as there is a ...
- 301
4
votes
Mitigating vulnerabilities in audio libraries that cause physical damage
The short answer is that you can't handle this in software.
I have a couple of headsets I use. One has a built in amplifier and noise cancelling; having my volume at 10% is perfectly fine for a audio ...
- 15.4k
3
votes
Is it possible to use steganography on an analog audio channel?
There are a few ways to do this. Use ring modulation to add a virtual carrier to the audio you want to hide, for example at 14khz. Goldwave's mechanize feature can do this. This will give an amplitude ...
3
votes
Does the iOS 10 keyboard click sound divulge too much?
While similar to old fashioned shoulder surfing, this attack has some severe limitations:
You need physical proximity - you need to hear the tapping sounds. That means it can not be automated.
While ...
- 65.4k
2
votes
Accepted
Audio Streaming Server associated vulnerabilities
See below example diagram. This way is good because:
Server to which you push stream is not the same as on the public internet, therefore you can make sure it's properly secured, like there's no ...
- 2,731
2
votes
Accepted
Media files : how to protect from 0-day?
There's no silver bullet for this, but the one reasonable approach is to convert all media into a canonical format in a sandboxed environment (e.g. a dedicated VM which is isolated externally and ...
- 135k
2
votes
Virus using input from victims mic to generate encryption keys
What you have invented is essentially a random number generator, and not "a true one way function". A one way function is something that alwasy generates the same output for the same input, but can ...
- 65.4k
2
votes
Does the iOS 10 keyboard click sound divulge too much?
If someone has a really good and valuable reason to be targeting you, they could use this to narrow down a brute force/mask attack.
For normal people, the chances that a password cracker (working for ...
- 83
2
votes
Virus using input from victims mic to generate encryption keys
A very interesting idea.
I suppose that malware could indeed obtain a very hard to reproduce key like this, however there could be some issues :
the target's microphone is muted
there is a very ...
- 1,619
2
votes
Is it possible to use steganography on an analog audio channel?
Off the top of my head I can think of two possibilities:
Hide the information in frequencies that the human ear cannot perceive (i.e. below 20 Hz or above 20 kHz)
Use the spread spectrum technique to ...
- 924
2
votes
Is it possible to put malware in an audio file with steganography?
Transmitting any data inside a playable audio file is already steganography by definition. Humans don't normally inspect the bytes inside an audio file, so any data placed in it that evades detection ...
- 34.1k
2
votes
How secure is the wireless Bluetooth data stream going from my computer to my headphones?
It depends, at least in part, on the highest version of Bluetooth is supported by both the dongle and the associated headphones. There are two main types in use, called BR/EDR (Basic Rate/Enhanced ...
- 66.5k
2
votes
Steganography in MP3s
There are a couple techniques for this that I'm aware of, one is called Backward masking. Not to be confused with the other, Backmasking.
Backmasking is arguably intentional. Regardless, it's a ...
- 870
2
votes
Accepted
secure Microphone Blocker for Apple devices (macOS and iOS)
The dummy, i.e. unconnected, microphone plug was a commonly recommended security method many years ago. It worked by mechanically breaking the circuit to the internal microphone in order to connect to ...
- 8,118
1
vote
secure Microphone Blocker for Apple devices (macOS and iOS)
You can easily build yourself a "mic lock" by getting the cheapest wired microphone solution that will work for your hardware (for example a Bluetooth dongle with a microphone that goes in. ...
- 22.8k
1
vote
What are the known ways to gain complete access to hardware audio?
No offense but I believe you are being a little paranoid. If someone had the knowledge to take control of your computer, what would he gain by changing the audio quality? It doesn't make sense, at ...
- 111
1
vote
Can a speaker be used as a microphone?
Speakers can't be used as a mic, but that's because they use amplifiers, which are one way only (someone please correct me if that's the case), but headphones will work as long as they use the ...
- 27
1
vote
How to find all the microphones in a room?
First, Assume that every "smart" device has a mic.
After that the only thing stopping you from finding all mics in a room is to which degree you are willing to be satisfied that you have no mics.
If ...
- 111
Only top scored, non community-wiki answers of a minimum length are eligible