Western Alliance Bank notifies 21,899 customers of data breach

Arizona-based Western Alliance Bank is notifying nearly 22,000 customers their personal information was stolen in October after a third-party vendor's secure file transfer software was breached. Western Alliance is a wholly owned subsidiary of Western Alliance Bancorporation, a leading U.S. banking company with over $80 billion in assets. The bank first revealed in a February SEC filing that the attackers exploited a zero-day vulnerability in the third-party software (disclosed by the vendor on October 27, 2024) to hack a limited number of Western Alliance systems and exfiltrate files stored on the compromised devices. Western Alliance found that customer data was exfiltrated from its network only after discovering that the attackers leaked some files stolen from its systems. In breach notification letters sent to 21,899 affected customers and filed with the Office of Maine's Attorney General, the company said it has since "determined that the unauthorized actor acquired certain fi ... Read full article.