Source: AudioContext Information

[chris124567]

The AudioContext API reveals information such as sample rate, number of audio inputs, number of audio outputs, and other channel information. I have seen scripts such as Maxmind and Augur that utilize this information.

I wrote some some code to get this information. Comparing across browsers, Firefox's results seems to be identical to Chrome's aside from the maxChannelCount. However, my iOS 13 iPhone has many differing properties compared with desktop Chrome, which seems to suggest some level of entropy. I think this data is largely stable but I am unsure whether it adds enough entropy to be considered as a source. This source seems to be good enough for Maxmind but I was wondering if you had looked into this source before or had any additional insight on its effectiveness as a fingerprinting signal.

[Finesse]

Hi Christopher, thank you for your research. The AudioContext API is in our backlog. Here are a couple more links:

• https://amiunique.org/fp
• https://browserleaks.com/javascript#audio

I've found out that it can get some entropy from device hardware and software in desktop Chrome. We need to conduct some additional researches before including the source into FingerprintJS.

[chris124567]

That's what I figured - it's difficult to rigorously test these things unless you've got lots of devices and configurations to compare. Thanks

[Finesse]

We have BrowserStack and multiple own devices