Major U.S. banks pause data sharing with this federal bureau after a cyberattack exposed sensitive information

Several of the largest U.S. banks are reportedly pausing or reassessing how they send sensitive information to the Office of the Comptroller of the Currency (OCC) following a major cyberattack on the regulator.

JPMorgan Chase and Bank of New York Mellon have halted electronic information-sharing with the OCC, Bloomberg reported. Bank of America is working to transmit data through what it considers more secure electronic channels, according to the report.

The moves come after hackers reportedly accessed more than 100 accounts within the OCC’s email system over the course of a year—a breach the OCC and U.S. Treasury have labeled a “major incident.” The attackers are believed to have obtained highly sensitive information about financial firms, though the identity of the hackers remains unknown.

Banks have expressed growing concern over the breach and the OCC’s handling of its disclosure, The Wall Street Journal reported. Many institutions are still unclear about the specific information that may have been compromised.

The OCC, an independent bureau within the Treasury Department, regulates and supervises more than 1,000 national banks, federal savings associations, and the U.S. branches of foreign banks. The agency is currently being led on an acting basis by Rodney Hood, a former member of the National Credit Union Administration Board.

Among the types of sensitive information banks send to the OCC are reports on cybersecurity practices and National Security Letters, which can include classified details related to terrorism and espionage, according to Bloomberg.