Pretty much anything will fail if the end device is compromised. It's probably good up to that point. Otherwise you will have to look into some sort of air gapp

Pretty much anything will fail if the end device is compromised. It's probably good up to that point. Otherwise you will have to look into some sort of air gapping to a physically secure device dedicated to messaging (e.g. Yubikey). As always, it depends on the threat model...