JPMorgan Chase warns customers of possible data exposure

JPMorgan Chase says a technical glitch may have exposed the personal information of some online and mobile banking customers.

In a notification letter posted on the Montana attorney general’s website, the company said "a technology issue" may have mistakenly allowed customers to see other customers’ personal information and account information on its website or in the Chase Mobile app, or receive others’ account statements. The company said it found no indication that customers’ information was used inappropriately.

Customers might have seen other customers’ balances and transactions as well as name and account numbers, the company said.

The problem lasted from May 24 to July 14, according to incident information posted on the Montana attorney general's website. JPMorgan has offered affected customers a year of free credit monitoring from Experian.

A JPMorgan spokesman declined a request for an interview but referred to the notification letter on the AG's website.

“We notified a very limited number of customers, including seven in Montana,” he said.

The letter did not specify how many people were affected in total or whether they were in multiple states.

The company suffered a similar incident for about three hours in February 2018.

Mishaps that allow customers to access other customers' files are typically caused by software configuration errors.

Klarna Bank in Sweden had an episode in late May in which its app users were able to see other users' account information when they logged in. Each time they signed in, they saw a different customer's account data. The bank chalked the issue up to a "mobile app bug."