Uninstall the Nightowl App, now.

https://lemmy.world/post/2919904

Uninstall the Nightowl App, now. - Lemmy.world

The NightOwl application has existed since 2018 and is used to automatically switch between light/dark modes on the operating system. It is an alternative to the built in macOS automatic mode which only switches when the user steps away from the computer. However, the application has been bought out by “TPE.FYI LLC” in late 2022 that forcibly joins your devices into a botnet for use of market research, without your knowledge (other than the TOS in small text on the download page) or express consent (this feature cannot be turned off, even when the app is quit). This is documented in their terms of service.

This is extremely shady. How do I know if other apps I have are making me part of a botnet?

You need to examine your devices packets and see what servers they're going to. You can do that through Wireshark on Windows, or use an external sniffer to examine them.

I'm not aware of any native apps for Mac that can do that, but maybe others will know.

You mean like Wireshark lol?
Wireshark Foundation / wireshark · GitLab

Wireshark's official code repository. You can keep the releases coming by donating at https://wiresharkfoundation.org/donate/.

GitLab
Didn't know they maintained Mac packages as well, that's great.
And Little Snitch and TripMode, and various other apps and *nix command line tools lol