Coinbase has said a security incident at analytics vendor Amplitude exposed a small subset of its customers' contact details, along with data belonging to other Amplitude customers. The exchange disclosed the incident on 28 October 2026.

Coinbase said it found no evidence of unauthorised access to its own systems and that customer funds were not affected. It said it is notifying affected customers and regulators. Coinbase has not disclosed how many of its customers were affected, and described only a small subset of customer contact details as exposed.

A vendor incident, not a Coinbase breach

The distinction matters: the incident is reported at Amplitude, a third-party analytics provider, rather than a breach of Coinbase's own platform. Customers should still watch for phishing attempts using contact details, a common follow-on risk after contact-data exposure, even when no funds or account access are involved.

Separate from the May 2025 breach

This is a separate incident from the breach Coinbase disclosed in May 2025, which affected under 1% of its monthly transacting users and carried estimated costs of up to $400 million, according to Cointelegraph. That earlier case involved a different set of circumstances and should not be confused with the Amplitude vendor incident.

Sources: Cointelegraph and Digit.