Coinbase says it was not breached after an incident at analytics vendor Amplitude exposed a small subset of customers' contact data

Coinbase said on the evening of October 27 that an incident at Amplitude, a third-party analytics provider, had exposed contact data belonging to a small subset of its customers. In a post from its support account on X, Coinbase wrote, "Coinbase has not had a data breach." It said it found no evidence of unauthorized access to its internal systems, that customer funds were not affected, and that it is notifying impacted customers and regulators, according to Unchained.

The sources do not agree on every detail. Coinbase has not published a count of affected customers or a list of exposed fields; some reports say email addresses and phone numbers, but Coinbase has not confirmed that. A claim that more than 70,000 users were affected has circulated on X, but Unchained found no report from the security firm SlowMist itself and Coinbase has not addressed the figure. FinanceFeeds says data from other Amplitude customers was also exposed. Unchained said Amplitude had not posted a statement on its blog when it published.

Contact details cannot move funds, but they are the kind of data scammers use to send convincing phishing messages, so unexpected emails or texts that claim to come from an exchange deserve caution. Coinbase has not said what customers should do.