DHS Probes Cyberattack on Intelligence-Sharing Platform

The Department of Homeland Security is investigating a cyberattack on its Homeland Security Information Network, a platform used by federal, state, and local agencies to share intelligence and coordinate emergency responses. Hackers accessed HSIN servers during late May and early June, according to reporting by Nextgov and Bleeping Computer.

The breach potentially exposed information shared on the platform.

A DHS spokesperson stated the department is aware of a recent cyber incident involving a specific, unclassified legacy information sharing environment. Officials immediately isolated affected systems, mitigated the vulnerability, and launched a forensic investigation.

It remains unclear what data was stolen or how much information was taken. DHS declined to provide additional details when contacted by reporters.

HSIN allows agencies to plan, coordinate, and share information about major events and respond to emergencies. A previous security lapse in 2023 revealed that the platform contained personal information shared among law enforcement related to surveillance of Americans.

The platform supported coordination for the World Cup games currently underway in the United States.

The breach comes amid multiple cybersecurity incidents affecting federal systems since January 2025. These include the sharing of classified information over unapproved messaging apps, access to federal databases by members of the Department of Government Efficiency, and a reported spill of passwords and credentials by a CISA contractor.

Earlier this year, the FBI notified lawmakers that it had declared a major cyber incident after exposing phone numbers of surveillance targets.