A phisher's dream.
The victim got a phone call in which the she got manipulated into authorising something in the BankID smartphone app. But what she was actually doing was authorising the attacker to log into her online bank account.
First after several years (of blaming the thousands of victims for their millions lost) did the system start using QR codes on the screen scanned by the smartphone.
Remember that the flow the magic link is part of is one you initiate, that causes you to get an email you are expecting.
That email, and the landing and confirmation page it links you to, can explain very clearly that you are only supposed to authorize this if you are trying to log in on known device in known location that is displaying recognizable number on the screen right now.
That makes it impossible to text or speak it to a phisher.
Bonus points if you show the symbol as a noisy animated glyph, something like [2], or a link to a DRM'd video showing a symbol. That would make it very difficult to view even with screen recording or remote desktop software.
[1] https://www.bombmanual.com/web/index.html#:~:text=On%20the%2...
There's nothing stopping anyone else from initiating the flow assuming the common implementation where only an email is required to initiate sending the link.
Here is the link you requested from ‘Android Device’ in ‘Belarus’ - click here to sign in and allow that device to access your account - only click this if you requested this email
You don’t click the link if you didn’t request it.
This is a simple quick login process, you wouldn’t use it in a place where 2FA is required. It is a mistake to think of this as a substitute for 2FA just because it has some of the same elements as a secondary device authentication. It’s not intended to be a 2 FA flow though! It’s a single factor - ‘does the user have access to a device that can read emails sent to this associated email address’. We aren’t combining it with a password or anything else.
That is the same level of auth used for things on many services like ‘registering for a free account’, and frequently for ‘resetting the password on an account’.
It’s not a complete security solution and you wouldn’t use it everywhere. It would be a bad fit for a banking app or access to a publishing interface. It’s not a bad interface for things like ‘logging in to my subscription on the TV’ or ‘returning as a customer to a website I shopped with once before’.
edit: saw that nicce basically said that a second before I hit post.