Is someone eavesdropping on you? Not on our watch!

Kaspersky Internet Security prevents eavesdropping through a computer microphone. Here’s how it works.

Is someone eavesdropping on you? Not on our watch!

It’s not paranoia if they’re really out to get you. Remember when people mocked others for covering up their webcams? After reading the news, no one was laughing; instead, they began covering up their webcams too — or using Kaspersky Internet Security’s feature that blocks unauthorized access to webcams.

But let’s not forget microphones. Tape doesn’t block sound, and moreover, persistent malefactors can even eavesdrop through speakers, which have essentially the same construction as microphones. Disabling the microphone with system software is no solution: an app can turn it back on.

Again, Kaspersky Internet Security comes to the rescue with patented technology that features system-level protection from eavesdropping. Here’s how it works.

The problem

First, a bit of background: More than one application can create sounds simultaneously — ever been watching a movie when a notification took you right out of the action? To handle simultaneous playback, an operating system operates with audio streams, and a system component controls the streams. If an app wants to make a sound, it creates an audio stream.

Audio streams can be linked to different devices, such as speakers or a microphone. Several simultaneous audio streams can receive data from a microphone, just like several streams can access speakers at the same time.

Looking at it from the other side, a microphone cannot create different streams for different applications; it is just a passive device that captures every sound it picks up. So all those streams it creates are identical. At the operating-system level, no protection exists against unauthorized access to the microphone: An app can create an audio stream, hook itself up to the microphone, and capture all that it “overhears.”

The solution

What can be done? Go to the source and trace the creation of new audio streams! That is what Kaspersky Internet Security does (of course, Total Security does it as well). The Privacy Protection component, which also includes the feature that blocks access to your webcam, is capable of tracing the creation of new audio streams as well.

Among other things, the component investigates which app is creating a new stream. It isn’t enough simply to block access to the microphone: To protect users from malicious applications but ensure legitimate applications retain access to the microphone, we have to determine the nature of any app requesting access to the microphone. From there, it’s a simple matter of allowing or denying access.

If the program in question is a trusted app from a well-known developer with a good reputation — and it doesn’t appear in antivirus databases — then its attempts to generate audio streams will not be blocked. However, if something is off about the app, such as a shady developer, a blemished reputation, or, worse, noted outright malicious actions, then Privacy Protection will trace the request for generating an audio stream and simply eliminate it.

We have implemented this technology in Kaspersky Plus, and we were recently granted a patent for the technology. Therefore, nobody can eavesdrop on those who use our products. This technology is enabled by default, so you do not need to activate it.