Klarna users are being signed in to random accounts

Their German counterpart, Sofortüberweisung, didn't properly blacklist test credentials given out by banks e.g. to developers in the beginning, so people could simply use those and pay for goods and services with fake accounts.

For me there are so many red flags with all these services, as they basically "steal" your credentials to log into your online banking. And while they claim that they only use the credentials to make transfers they could as well look at all my other account data. I really wonder how such a scheme can be legal and how banks can allow this, as they normally tell people to never give their credentials to anyone. The situation of course recently improved with the mandated 2FA for logins and transfers, but still there are so many attack vectors in this model that it boggles my mind how it can still exist.

There have been some weird legal cases in Sweden where businesses and scammers have been freed after having signed in using other people's "BankID" to change retirement savings around or send cash.

Its the ID method I use for credits, pharmacies, health care, taxes, but was apparently not an ID so it's not id-hijacking.

Klarna has man in the middled my bank account before and performed a purchase and I've boycotting any company having them as the only payment option since.

OH, now I also remember Klarna adding credit in my name since they only needed my tax registered adress. I lived in a dorm so someone just used our public information to take out credits to order sneakers and could break into the crappy entry mailbox.

In Denmark, you're forced to use the state-run "NemID" for credit card payments, making for some weird situations where you authenticate with NemID inside iframes on shady URLs.

The same NemID is also used to file your taxes, look at all your health info, get married, everything basically.

Credit card payments are much lower security level, and they're basically forcing sharing credentials amongst all the sites you pay on.

However it also forces everybody to use two factor authentication. On a whole population level I'd bet that's overall a positive tradeoff.

And I believe you can also use sms + password for online transactions.