3 ms·

Really interesting, this is the first time I hear anything about what is in those Realtek firmwares. Keylogger aside, is there anything fun or nefarious one cou

Really interesting, this is the first time I hear anything about what is in those Realtek firmwares. Keylogger aside, is there anything fun or nefarious one could do with the radio? Also, we use them at work in our products, and usually just get the firmware and driver binaries thrown over the wall by the board vendor, withouy any description or changelog. I'm tempted to throw a few different bins through Ghidra and see if I can tell what changed.

GekkePrutser 5y ago
Considering people have been converting the PWM pin of a raspberry pi into a digital TV transmitter and the fact that all modern wi-fi chipsets are software defined, I think a lot of malicious stuff can be done with it if one really sets their mind to it. Much more than the regular deauth shenanigans.
- pfundstein 5y ago
  I think I found the transmitter you're talking about, it looks pretty neat: https://github.com/F5OEO/rpidatv https://github.com/F5OEO/rpidatv
  - GekkePrutser 5y ago
    Yes, it's very cool! But don't use it to transmit in practice though. The output is very dirty because it produces square waves which generate a lot of harmonics (emissions on unintended frequencies). You can use this safely if you know what you're doing but only with a lot of filtering. Or by not transmitting as such but outputting into a receiver directly with some attenuation.
- Nextgrid 5y ago
  > Considering people have been converting the PWM pin of a raspberry pi into a digital TV transmitter Somehow the world didn't end though? Maybe we should just assume the RF spectrum can and will be interfered with regarding of regulation and design accordingly, rather than trying to put the cat in the bag? After all, that's the approach we take for security despite "hacking" being illegal in most countries, and yet we still use HTTPS and authentication.
  - SilverRed 5y ago
    There is a difference between transmitting on the TV band with a range of one room and sticking a transmitter tower up in your back yard. No one cares or can even detect low power unauthorized transmissions.
  - GekkePrutser 5y ago
    I never said the world would end. I just answered the question about repurposing the hardware.

GekkePrutser 5y ago

Considering people have been converting the PWM pin of a raspberry pi into a digital TV transmitter and the fact that all modern wi-fi chipsets are software defined, I think a lot of malicious stuff can be done with it if one really sets their mind to it. Much more than the regular deauth shenanigans.

pfundstein 5y ago
I think I found the transmitter you're talking about, it looks pretty neat: https://github.com/F5OEO/rpidatv https://github.com/F5OEO/rpidatv
- GekkePrutser 5y ago
  Yes, it's very cool! But don't use it to transmit in practice though. The output is very dirty because it produces square waves which generate a lot of harmonics (emissions on unintended frequencies). You can use this safely if you know what you're doing but only with a lot of filtering. Or by not transmitting as such but outputting into a receiver directly with some attenuation.
Nextgrid 5y ago
> Considering people have been converting the PWM pin of a raspberry pi into a digital TV transmitter Somehow the world didn't end though? Maybe we should just assume the RF spectrum can and will be interfered with regarding of regulation and design accordingly, rather than trying to put the cat in the bag? After all, that's the approach we take for security despite "hacking" being illegal in most countries, and yet we still use HTTPS and authentication.
- SilverRed 5y ago
  There is a difference between transmitting on the TV band with a range of one room and sticking a transmitter tower up in your back yard. No one cares or can even detect low power unauthorized transmissions.
- GekkePrutser 5y ago
  I never said the world would end. I just answered the question about repurposing the hardware.