FBI Classifies Surveillance Cyber Breach as Major Incident

The Federal Bureau of Investigation has classified a cyber intrusion into its internal surveillance systems as a major incident under the Federal Information Security Modernization Act, determining that the breach poses significant risks to U.S. national security. Officials suspect Chinese government-linked hackers carried out the attack, which was first detected on February 17, 2026, and involved access to sensitive data related to ongoing investigations.

The FBI notified Congress of the incident on March 4, 2026, and briefed lawmakers the following week after confirming it met the FISMA threshold for a major incident. This designation requires federal agencies to report intrusions likely to cause demonstrable harm to national security, foreign relations, public confidence, or civil liberties within seven days. According to a congressional aide and two U.S. officials familiar with the matter, the hackers gained entry by exploiting the infrastructure of a commercial internet service provider vendor, a tactic indicative of advanced persistent threats.

The compromised network, an unclassified system used to manage court-authorized surveillance operations, includes the Digital...