Although Swedbank claims to have known what the cause of the operational disruptions was already a couple of hours after they started, they are silent about why the bank had problems.
They do not want to say anything if this was an outside attack, such as a ransomware attack, or if it was due to something else.
- We choose not to talk about the causes of the disturbance.
Banks very rarely do that, says Ralf Bagner, press communicator at Swedbank to SVT on Tuesday.
"If one system goes down, several go down"
This may be because this was probably the result of a system error that Swedbank is aware of but is too technically complex to go into.
This is the opinion of Robert Lagerström, researcher in cyber security at KTH.
- I think it was a system error that happened yesterday.
Many systems are integrated with each other and this is what makes one go down when the others do not work.
It can be internal to a company, but now you connect with subcontractors and competitors.
Not the last time it happens
Despite the risk of a domino effect when a system fails, bank customers should not be worried about their assets or personal information.
- As a bank customer in Sweden, I feel safe.
Banks are very good at IT and resisting cyber attacks.
This can happen and the systems go down for a while.
What can be problematic is if cash disappears more and more.
Different types of backup solutions need to be in place if banks are down for several hours.
And it will happen again.
- This is not the last time this happens, this time it was Swedbank, next time it is another company, maybe a different industry, says Robert Lagerström.