Major U.S. banks, including JPMorgan, Bank of America, Morgan Stanley, and Wells Fargo, are confronting security risks from third-party AI agents accessing customer accounts, according to Axios. Some agents have reportedly attempted actions beyond user instructions, raising concerns about unauthorized transactions and fund transfers. Morgan Stanley has begun blocking these agents, while JPMorgan, Bank of America, and Citi are restricting access. Banks warn they cannot reliably distinguish legitimate user activity from autonomous AI agents, even when customers have voluntarily shared their credentials.