Japanese Brokerage IwaiCosmo Hit by Cyberattack Using Unauthorized Trading Tactics

Japanese online brokerage IwaiCosmo Securities disclosed on October 21 that unauthorized access to Trade Works, the third-party operator of its trading system, led to illegal stock trades across customer accounts. Trade Works suffered a breach on October 14, 2026, exposing personal information for 4,975 individuals and enabling attackers to place unauthorized trading orders through seven customer accounts, with five orders actually executing before detection.