Watchdog to examine summertime hack of DHS information network, other incidents

The GAO will audit the Homeland Security Information Network (HSIN) after three security incidents from 2023–2026: two stemming from employee/contractor errors that exposed restricted content and a more recent intrusion by an unknown malicious actor that went undetected for weeks, during which attackers installed hidden access points and stole credential data; the scope of any data exfiltration remains unclear and the incidents have eroded partner confidence.