If all of your credit lines, checking, savings, and investment accounts were an API call away, the institutions providing those no longer build relationships that can be profitable; they're simply utilities you could swap out interchangeably. As such, they're not a fan of this idea.
It's sad, because that's exactly what they should be. :/.
As for this instance specifically, I believe Chase grants Mint (and few other whitelisted companies) account access via OAuth. It's a step in the right direction, although it's not clear to me what their long term goal is.
AMA, I guess.
But to answer the implicit question: shutting that off can be harder than it sounds. And because it's a mobile API and iOS's store has fairly slow update cycles, it can be very hard to simply rotate your API spec fast enough without interrupting customer service: a difficult thing for a bank to get away with (lol, I'm joking they're down all the time).
You can also use your own canary accounts, provide them to the service you want to block, and ban any IP that tries to log in
Enjoy your customer service costs. On the plus side, bank have really good customer retention once they capture a customer.
If it's a big enough bank, the threshold should be higher. But they can easily pull the data and set a threshold that cuts off only the peak of the distribution
My prior investigations suggest that this strategy is ineffective. You suss out a ratelimit then pick a CSP and start spawning instances. Bonus points if it's a CSP that has a contract with that bank, they'll be petrified to try blocking you. Even well run consumer orgs can get tripped up with that.
But you're also suggesting that banks can use that data in that way or that that the relevant parties had the necessary capability at the time in question. Both are propositions you can make your own judgement on.
Here's another question: what happens when customers complain that you're cutting off their aggregtion service? You have your customer service reps say, "Sorry we locked you out of getting your own data?" Sounds like if you do that enough we have another press row. Thank goodness the CFPB was gutted, they loved 3rd party resale-to-consumer aggregtion services.
A lot of the measures taken to prevent fraud also block proxies and the like.
Re customer service: they say "here's how you can download your statements in pdf format", or for many banks in quickbooks/excel/etc format as well
I don't know how many of them had mandatory 2FA then, but I think many more have now. It would be far less risky to invalidate cookies on those high-volume IPs and force a new 2FA validation. Then legitimate users could reverify.
Look there are limits to what I'm able to talk about, but consider that a fraud subsystem functioning in transaction-time is running much more slowly than something running in request time.
> A lot of the measures taken to prevent fraud also block proxies and the like.
When was the last time you couldn't use your banking website over a proxy? Only a few mobile apps actually make the decision to do this (mine did) and it's not popular.
> I don't know how many of them had mandatory 2FA then, but I think many more have now.
Which national bank has mandatory 2fa? Not that this would matter. We dealt with 2FA at level via Intuit, that wasn't great at it. Plaid got incredibly good at it. It became pedestrian when we experimented with Plaid.
I was suggesting checking one day snapshots of access counts by IP to see what the distribution looks like to then determine what to block.
2fa: I know that chase asks me for 2fa every time I change IP, and I don't think there's a way to stop that. Should be easy for them to require 2fa on every login for any IP with a high rate of requests.
What do you think of the canary account I suggested?
I don't know how such a canary account would ever end up as a target for financial aggregation. It'd probably be a lawsuit from the aggregator for TOS violation if it was a sting operation.
>lawsuit
You really think an aggregator who's blatantly violating bank TOS is going to sue?
And while I know I did a cert pin and you did a cert pin, not everyone does it (or does it bidirectionally). Nor is that the only way folks would get an API spec.