The Defcon talk from the researcher is also quite good. They reverse engineered the firmware update system for some of these devices as well and published patches.
The DEF CON talk is https://www.youtube.com/watch?v=00A36VABIA4
Yep, that’s the one.
The good thing now is that fwupd (on Linux) can actually update the firmware in the Logitech dongles to fix exactly this vulnerability: https://blogs.gnome.org/hughsie/2017/05/22/updating-logitech-hardware-on-linux/