U.S. Department of Homeland Security’s HSIN network hacked

The U.S. Department of Homeland Security confirmed a cyberattack on its Homeland Security Information Network (HSIN), a platform used to share sensitive but unclassified information among federal agencies, local governments and private partners. Attackers breached the HSIN servers and a SharePoint collaboration environment; no classified networks were impacted. The department isolated the affected systems and launched an investigation, but has not identified the threat actor or determined whether any data was exfiltrated.

The intrusion occurs as DHS coordinates security for high‑profile events, including the FIFA World Cup hosted on U.S. soil and the America250 celebrations. Senator Mark Warner warned that the compromise could jeopardize national security if information were leaked. The incident follows previous HSIN‑related security lapses, such as a 2023 configuration error that exposed sensitive data.

No evidence so far indicates state involvement or the theft of classified material, but officials stress the need for enhanced cybersecurity safeguards across federal information‑sharing networks.