Do modern (versions of) operating systems, primarily Android and iOS on mobile, still send targeted or directed probe requests when searching for Wi-Fi networks to connect to?
Such targeted or directed probe requests contain the SSIDs of known networks, and may thus leak information about the sending device’s location history, the owner’s social relationships, etc.
According to this source, modern operating systems do not send these requests anymore:
Around 2014, the privacy implications of targeted probe requests started to become widely publicized and understood. Most new devices therefore stopped sending them. […] When the privacy implications of targeted request probes became widely appreciated, most new mobile devices stopped sending them altogether. […] Targeted probe requests are mostly a thing of the past.
Other sources, like this one or this one, seem to confirm that targeted probe requests are not sent anymore on the latest versions of Android, at least.
If this is indeed true, and perhaps also for iOS (and some desktop OSs), are there any press releases, bug tracker entries, security reports or code commits that confirm this?
Directed probe requests, as opposed to broadcast requests that don’t contain a network’s SSID, should only be necessary for hidden networks. The impact is stronger on mobile devices, where you tend to both have more known networks added to your device and broadcast that list in more places.