Payments with Stolen Phone

My phone got stolen, which caused all kinds of trouble. The thief managed to make wireless payments with the phone. The way how he was able to do that remains a mystery.

The theft was a pickpocket job. It took some time until I realized that my phone was stolen. Luckily, I was not traveling alone, therefore I could borrow a phone to quickly contact my banks and company to lock out all access. However, it turned out it was already a bit late. I had my phone set up for contactless payments, and a significant sum of money was already gone.

My phone was locked at the time it was stolen. I'm not sure about many details of the events that happened, I'm not even sure when exactly the phone was stolen. However, I'm very confident it was locked. I'm always explicitly locking the phone by pressing the lock button. I always press the button when I put phone in my pocket, I'm pressing the button even if I put the phone on a table in front of me, I'm pressing the button even when I'm at home alone. It is automatic. The phone was locked.

My phone was Fairphone 6 running Murena /e/OS. My phone was set up for biometric (fingerprint) unlock and PIN unlock. The PIN was non-trivial. There was additional biometric confirmation of payments in the payment app itself. The payments were authorized minutes after the theft (my best guess, as I do not know when exactly was the phone stolen).

How was the thief able to make substantial payments with a locked phone in such a short time? I thought that this is very unlikely, yet it happened. I'm considering several possibilities:

It is a mystery. I cannot really explain what happened. It should not be possible, yet it happened. When I got home and changed all my passwords all around the Internet, I have contacted all involved parties:

There is kind of a happy end to this story. The fraudulent payments were rolled back and refunded. I got lucky this time. However, my concerns regarding security of mobile payments remain. I still do no know what happened, and it looks like I will never find out. My phone is gone, no way to learn anything there. The bank and the payment provider are obviously not inclined to share any more details. This route seems to be closed.

Although I do not know what happened, I have an impression that this experience is a consequence of the overall approach taken by fintech and mobile industry. I think that the fintech is motivated to trade off security for convenience. Easier access to payments mean higher revenues for fintech. Of course, there is an increased risk when a convenience takes precedence over security. However, the risk could be easily "mitigated" by shifting it over to the consumers. I was lucky, the transactions were refunded in my case. Will I be so lucky next time? I do not know. What I know for sure is that I'm not going to risk it again. I've got brand new Murena Fairphone now, all applications re-installed and ready to go. All except one. I'm not going to risk mobile payments again.