4 ms·SMS is not two factor authentication, no matter what ISPs or websites tell you.by inetknght 8y agoSMS is not two factor authentication, no matter what ISPs or websites tell you.chayesfss 8y agoActually it is a form of 2fa, might not be one you like but it’s better than 1fa or kba which is double single factorweej 8y agoAgreed. Although poor security with easy hijacking, it's still a form of 2FA. Even NIST doesn't recommend it as a factor to use for authentication.