I can think of easier ways of compromising the data besides brute forcing the keys, off the top of my head, and I’m just some schmuck. Relevant XKCD: https://xkcd.com/538/
Compromise their endpoint with a malicious app on the app store.
Gain physical access to the device and compromise it. Use your imagination – pickpocket, traffic stop or customs inspection by a compromised agent, seduce them with a honeypot, etc.
Socially engineer them to mistakingly add you to their group chats.
SIM swap
Signal might be fine for journalists, criminals, cheating spouses, and general privacy when used properly with good OpSec but nation state adversaries have significantly greater resources than your average attacker, and thus require more significant security.
Even if they do get access to the chat logs, good luck brute forcing those encryption keys Putin!
I can think of easier ways of compromising the data besides brute forcing the keys, off the top of my head, and I’m just some schmuck. Relevant XKCD: https://xkcd.com/538/
Compromise their endpoint with a malicious app on the app store.
Gain physical access to the device and compromise it. Use your imagination – pickpocket, traffic stop or customs inspection by a compromised agent, seduce them with a honeypot, etc.
Socially engineer them to mistakingly add you to their group chats.
SIM swap
Signal might be fine for journalists, criminals, cheating spouses, and general privacy when used properly with good OpSec but nation state adversaries have significantly greater resources than your average attacker, and thus require more significant security.
Well, he just needs to get them to accidentally add his spy to their group chat. How hard can it be?
Wasn’t there a hacker group some years ago that released Signal binaries with backdoors that allowed attackers to read decrypted messages?