lynis VS mitmproxy

Linux has (free) tools to improve security and detect/remove malware: Lynis,Chkrootkit,Rkhunter,ClamAV,Vuls,LMD,radare2,Yara,ntopng,maltrail,Snort,Suricata...

What I would do in your place is run this https://github.com/CISOfy/lynis and follow some of the instructions.

https://github.com/CISOfy/Lynis (Linux hardening)

Linux security audit scanner

This statement gives a false sense of security. You can use a transparent proxy, like mitmproxy, to view HTTPS traffic - https://mitmproxy.org/. https://reedmideke.github.io/networking/2021/01/04/mitmproxy-openwrt.html

You'll need to install mitmproxy and set it up on your computer and iOS. I won't go into too much detail here on how to do this, but there are plenty of guides available. This is a pretty good one: https://nadav.ca/2021/02/26/inspecting-an-iphone-s-https-traffic/

TIL this goes back to 2006, how cool! We nowadays have a much simpler version as a mitmproxy example: https://github.com/mitmproxy/mitmproxy/blob/main/examples/ad.... Although it obviously does not work as well anymore with everything being HTTPS nowadays (unless you trust the cert of course). :)

Perhaps you could have your device use a proxy that can do the HTTPS unwrap for you? https://mitmproxy.org/ maybe?

A great way to test the effectiveness of a pinning implementation is by simulating an MITM attack. Tools like Mitmproxy or Wireshack allow us to create a test environment to monitor, intercept, and proxy network requests for a test host.