It has become a drearily familiar story: A data breach at a major company exposes troves of sensitive information, putting millions of people at risk of online fraud.

Last year, it was Marriott. The year before, Equifax.

This time, it’s Capital One, which said on Monday that a hacker had compromised the personal information of more than 100 million people, in one of the largest-ever thefts of data from a bank. For the vast majority of those consumers, the breach appears to have exposed only relatively inconsequential details like names and addresses, rather than Social Security and bank account numbers.

The bank said it was “unlikely that the information was used for fraud or disseminated by this individual,” and that no credit card numbers or passwords were exposed.