Security experts this month tested 275 Apple iOS- and Android-based mobile banking apps from 50 major financial institutions, 50 large regional banks, and 50 large U.S. credit unions. Overall, they found that eight out of 10 apps were improperly configured and not built using best practices software development. Among the big-name banks whose mobile apps were tested by security firm Praetorian include Bank of America, Citigroup, Wells Fargo, Goldman Sachs, Morgan Stanley, Capital One Financial, and Suntrust Banks. Praetorian did not disclose how each bank’s apps fared in the tests.

Nathan Sportsman, founder and CEO of Praetorian, says the security weaknesses in the mobile banking apps he and his team tested are not pure software vulnerabilities, so they are relatively low-risk issues that could ultimately lead to exploitation.