25 days ago
- Signal saves sensitive information permanently in account databases, including phone numbers and group metadata.
- Deleting groups or chats only hides information; full deletion requires deleting all app data and re-registering without PIN.
- Signal uses SMS authentication, making accounts vulnerable to takeover through SIM swaps or SMS interception.
- ACIs (Account Identifiers) are tied to phone numbers and can be shared with governments upon request.