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Comment by thaumasiotes | Hacker News Reader

> Like how banks have that "only type your password if we show your correct profile picture".

Do they? My banks did that years ago, and they also stopped doing it years ago.

They are ineffective.

>Of the 63 participants whose responses to prior tasks had been verified, we were able to corroborate 60 participants’ responses to the removal of their site-authentication images. 58 of the 60 participants (97%) entered their passwords, de-spite the removal of the site-authentication image

See https://security.stackexchange.com/a/19801 which summarises https://sites.google.com/site/ianfischercv/emperor.pdf

Some still do. I don't see the point though - a determined attacker could just make http requests to your bank and substitute the parts they want to. Would be on the attack domain still so still technically phishing... But if the image is an anti phish measure it's not a great one. I suppose it could raise the bar to a successful attack a bit but certainly doesn't make it impossible.

Isnt't that what CORS/same-origin policies prevent? The attacker domain can be prevented from loading the bank resources within the same context by the browser. If the request is made by the attacker domain instead and proxied to you, then it doesn't have your cookies to display the private identification.

In either case, the "correct profile picture" would not load.

Most people would not question having to type in their username for a fresh login - Banks sign you out so quickly and their "remember me" is often intentionally gimped. So users are trained to type their username into the field, and the bad site can proxy that to the bank and send back the image just fine.

Okta still includes this "feature" by default, and is among the reasons I will never trust Okta or any client of theirs.

You can keep iterating on this if you like, and some banks did, but ultimately the bad guy has the exact same information you've presented to the bank to get this "correct profile picture". Cookies. CORS headers. None of that matters. If you get the "correct profile picture" so does the bad guy and then they just forward it to you.

We already know how to actually solve this problem. WebAuthn.

> If the request is made by the attacker domain instead and proxied to you, then it doesn't have your cookies to display the private identification.

Why is that a concern? You try to log in on a phishing site. The phishing site tries to log in as you at your bank's actual website. Your bank sends the phishing site your picture. The phishing site displays your picture to you.

The bank can and will use quite sophisticated request flow analysis to prevent one party from making too many attempts, so this means an attacker must grab a botnet or similar and be careful to avoid detection.

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