Monzo advising customers to change PINs over security breach
Monzo is writing to customers to encourage them to change their PIN numbers after discovering a potential security flaw.
On Friday a Monzo engineer discovered that copies of PINs for some customer cards had been made and stored in locations that were accessible to the bank's tech staff.
In a statement, it said: "We ask for your PIN whenever you want to make a payment, or do anything else that’s sensitive on your Monzo account.
"And as your bank, we keep a record of your PIN so we can check you’ve entered it correctly. We store them in a particularly secure part of our systems, and tightly control who at Monzo can access them.
"On Friday 2nd August, we discovered that we’d also been recording some people’s PINs in a different part of our internal systems (in encrypted log files). Engineers at Monzo have access to these log files as part of their job."
The bank says there has been no evidence that any data was breached.
But it is writing to half a million of its customers encouraging them to change their PIN numbers.
Affected customers should change their details immediately at a cash point, the bank says.