EY Data Breach Claimed by ShinyHunters Hacker Group

ShinyHunters publicly claimed responsibility for a supply-chain compromise of a third‑party IT support platform used by EY, alleging unauthorized access from March 28–April 12, 2026 that exfiltrated employee credentials and client tax documents containing names, addresses, Social Security numbers, and financial account data; the group posted a July 31, 2026 extortion deadline. EY detected anomalous activity on April 23, 2026, notified regulators of at least 1,366 affected US residents, offered credit monitoring, and has not confirmed ShinyHunters' specific claims or reported misuse of the data.