Open source is free of backdoors. As for '*they', I've heard all kinds of whistleblowers but none about backdoors that record everything before encryption. The closest thing would be from the Wingmakers Disclosure/ Ancient Arrow Project where Professor Andrew talks about a computer program that can expose how any other program runs and replicate it and potentially use to spoof and such, but that's not hardware as far as I can tell, which is what you consider is compromised.