Stop requiring a phone number to set up 2FA.
First of all, good job on implementing non-Authy, non-SMS 2FA!
That being said, there's still a major hole in your 2FA implementation, and that's requiring a user to set up SMS authentication before they can set up other forms of 2FA. Unless I've missed something huge, whenever I try to set up 2FA on Twitch, I get directed to put in my phone number first. There's no prompt I can use to skip this step.
This is completely counter to how a lot of other sites do 2FA, where SMS authentication is an option, not a requirement. You can completely ignore SMS authentication and just use a standard TOTP code to set up Google Authenticator, etc. I would like to see Twitch adopt this practice as well: instead of requiring us to put in our phone number first, please just give us a list of 2FA options and let us pick a method without requiring the others. Or at least give us the option to set up SMS, set up an alternate 2FA method, and then remove SMS afterwards.
Not requiring SMS is important for several reasons:
It's one of the most insecure forms of 2FA. Relatively speaking, it's significantly easier to intercept a SMS or gain control of someone's number than it is to crack a TOTP token. (See this article for examples: https://arstechnica.com/information-technology/2018/08/password-breach-teaches-reddit-that-yes-phone-based-2fa-is-that-bad/) Requiring SMS means that everyone's account now has that "weakest link," even if they use a TOTP app.
Not everyone is comfortable giving their phone number to Twitch. Phone numbers are used for all sorts of things these days, including sensitive accounts. Some people just might maintain a strict online/offline life separation, and are wary of their phone number being leaked. Even if Twitch never intentionally reveals SMS authentication numbers to the public, hacks can and do happen.
Not everyone has a phone, or has a phone capable of receiving text messages, or a permanent phone number, or a phone that's recognized by Twitch as legitimate... Some people are still on landline for financial reasons. Some people are using small, alternative carriers like Republic Wireless or Google Fi, which get flagged as VoIPs. (Which Twitch does not allow for SMS authentication, despite those numbers being able to receive text messages.) The possibilities go on and on.
I'm sure there are many other reasons why requiring SMS authentication is a bad idea. I'm not asking for it to be removed entirely, but we should at least have the option of NOT using it.
Thanks for reading, and do correct me if this option already exists and I somehow missed it.
This. 1,000,000x this. Phone number shoud NOT be required. Let us just have that and download our backup codes. Done and done. this is just an information grab and is disgusting.
Hello Twitch? Since you won't allow my Republic Wireless number. Same phone number I have had for 20 years. Let us use an authenticator app. Perhaps hire a better security team too. You have so much egg on your face right now.
With today's news it's probably a good idea to revisit this, Twitch. Way more people have no access to a non-VOIP SMS-capable number than "would seem".
Things like this are a clear indicator of management making decisions they do not understand (or worse they do understand it and are selling our data), and it has been extremely effective at keeping me off the platform entirely.
2FA with zero SMS requirement, or nothing.
Wait, Twitch doesn't allow the use of Google Voice for 2 FA? That makes sense now.