Is phone/text based 2 Factor Authentication generally weaker than using an authenticator app?
I'm trying to work out why a major site would not offer 2 Factor Authentication via phone/text, but offer other methods (authenticator app) instead?
Because of the reason explained tersely above.
Namely, using phone/text 2FA is less secure than using a good ...
App-based 2FA is much stronger than SMS/Phone based 2FA.
The reason being that 2FA code sent to SMS and phone call can be intercepted by your mobile phone network provider. By design, because phone number assignments are controlled by your mobile network provider. What this means is that you're subject to any vulnerabilities in the phones network provider, ...
As of now, it is way safer to enable MFA with an authenticator app compared to SMS, mainly because this specific network technology (SS7) is vulnerable for interception, but also to SIM swapping attacks.