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This is insanely weird, and although it's not necessarily a problem, I'm really curious what's going on here.

I'm running Ubuntu 21.04 and have a wireless Logitech keyboard and mouse along with the Logitech unifying receiver. I'm running Solaar to help manage those. I work for a company that provides a MURS walkie-talkie for work onsite.

This evening, I was playing around and turned the walkie-talkie on and tapped the talk button. My screen went nuts. The application that was open closed, and a string of random text appeared in a background application. I'm not too knowledgeable with wireless technologies, but it seems really strange that my walkie-talkie can cause interference and interact with my PC. Does anyone have any insight on this?

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RFI (Radio Frequency Interference) is actually common. For example from this article:

"The walkie-talkies in the article yesterday are Motorola FRS (Family Radio Service) transceivers and operate in the 400Mhz range (around 460mhz). At these frequencies the wiring in computers and TV sets can act as antennas. The higher the frequency the short an antenna has to be to be resonant. Depending on the power level of the transmission this can cause all kinds of problem with frequency dependent devices - such as monitors, mice, keyboards and the like.

"The frequencies of the two devices can mix and cause problems by adding to or subtracting from the frequencies the device is expecting. This could cause the screen to distort and could also lead to false mouse movements and clicks and well as false keyboard entries.

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    Thanks for the reply. I have a similar setup at work (although using Windows, not Linux) and I can't remember anything like this happening before. I'll be bringing my keyboard and receiver to test tomorrow. This seems like a potential vulnerability, being able to arbitrarily interact with a computer without any sort of pairing or direct access to the machine.
    – Andrew S.
    Aug 6, 2021 at 4:50
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    Interference don't surprise me... But I would have thought that there would be a minimal security with the unifying receiver (logitech are soo common, we shouldn't be able to communicate without pairing). BUT maybe there is a encryption with windows that you don't get with Linux/Solaar
    – sayanel
    Aug 6, 2021 at 12:40
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    @sayanel no, it doesn't work that way. The encryption isn't a software feature :) But the packet integrity isn't very strong, just a CRC16 (I think; the chip also supports CRC8 and no CRC, which would be even weaker), so if you get it to decode a continuous stream of noise, some of it is bound to appear as valid packets. The encryption just means that you can't control their content.
    – hobbs
    Aug 6, 2021 at 14:11

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