So, iiuc, this "zero-click" hack involved iMessage and payloads apparently injected via Apple's domains and the exfiltration of data through a tor-like network eventually reaching malicious servers. Is anyone aware of any (FOSS) software (presumably intrusion detectors or indicators of compromise) for mobile phones that might help flag or even prevent such attacks? TinyCheck [0] comes to mind, but it isn't truly mobi…
Most likely the malware is using SSL so packet sniffing from an external device isn't gonna work. And it's apple, so at best you might find a firewall among their tightly locked down app store. Don't worry, apple knows what's good for you far better than you ever could ::eye roll::
They should really hire more security folks. A lot of Apple's product security work seems to be outsourced to Google Project Zero.