AT&T says criminals stole phone records of ‘nearly all’ customers in new data breach

AT&T confirmed a massive data breach tied to a Snowflake account compromise that exposed phone numbers and call/text metadata (including call durations and some cell site IDs) for roughly 110 million customers covering May–October 2022 and limited January 2023 records; content of calls/texts was not stolen. Mandiant reported the Snowflake thefts affected many customers and attributed sizable data exfiltration to a financially motivated group tracked as UNC5537; AT&T is notifying customers, working with law enforcement (one arrest reported), and currently does not believe the data is publicly available.