For months, hackers stole internal data from dozens of companies, including AT&T, Ticketmaster, Advanced Auto Parts, and around 165 other corporate customers who use Snowflake, a company that provides cloud services and data analysis to other companies. The hackers stole huge amounts of often personally identifiable and sensitive corporate data that companies stored in Snowflake, in part by using passwords stolen from employee computers with malware. Because Snowflake did not require its customers to use multi-factor authentication on their accounts, the hackers were able to break in and steal large volumes of data using just the employee passwords.