Great. Now Even Your Headphones Can Spy on You

Realtek drivers on Linux, at least for some codecs, have this feature built-in, no malware needed. On my Dell XPS 13 9350, for example, I can use alsamixer or pavucontrol to choose between &quot;Internal Mic,&quot; &quot;Headset Mic,&quot; and &quot;Headphone Mic.&quot;<p>The &quot;Headphone Mic&quot; setting is designed for connecting a microphone to the single multi-purpose 3.5mm jack, but it can also record audio from a pair of headphones just fine if you turn the gain up.

Huh.<p>I remember back in the old days of the internets back when a cable modem meant you were bougie.<p>When we were playing tetrinet, some people didn&#x27;t have mics but somehow hacked a set of headphones to work as a mic. I remember the audio quality wasn&#x27;t -great- but what was back then?<p>I&#x27;d guess at least some of this is based on hacking the audio drivers that let the ports be &#x27;controlled&#x27;, i.e. how on some desktops when you plug a speaker in it asks whether you plugged in a speaker or a mic.

&gt; Their malware uses a little-known feature of RealTek audio codec chips to silently &quot;retask&quot; the computer&#x27;s output channel as an input channel, allowing the malware to record audio even when the headphones remain connected into an output-only jack and don&#x27;t even have a microphone channel on their plug.<p>This is a pretty big deal.