Hackers Hit Hundreds of Cisco Firewalls in US Government

Hackers compromised firewall devices within the US government, according to a senior federal official, amid broader warnings of cyberattacks on widely-used devices manufactured by Cisco Systems, Inc.

The US Cybersecurity and Infrastructure Security Agency, or CISA, issued an emergency directive Thursday requiring federal agencies to address vulnerabilities and identify and mitigate potential breaches in hundreds of Cisco firewall devices active in the US government. Cisco said in a security alert that the company was engaged in May 2025 with “multiple government agencies” to investigate attacks on the firewall devices.