The Enhanced Visibility and Hardening Guidance for Communications Infrastructure is promoted as providing best practices to protect against a People’s Republic of China (PRC)-affiliated threat actor that has compromised networks of major global telecommunications providers.

The guide is targeted at network engineers and "defenders of communications infrastructure to strengthen visibility and harden network devices against an envisaged broad and significant cyber espionage campaign, which CISA and FBI say they recently warned of.

In addition, the guide recommends actions to quickly identify anomalous behaviour, vulnerabilities and threats, and to respond to a cyber incident.

It also provides advice to organisations about reducing existing vulnerabilities, improving secure configuration habits, and limiting potential entry points.

“The PRC-affiliated cyber activity poses a serious threat to critical infrastructure, government agencies, and businesses,” said CISA Executive Assistant Director for Cybersecurity Jeff Greene.

"This guide will help telecommunications and other organisations detect and prevent compromises by the PRC and other cyber actors.

“Along with our US and international partners, we urge software manufacturers to incorporate Secure by Design principles into their development lifecycle to strengthen the security posture of their customers.

"Software manufacturers should review our Secure by Design resources and put their principles into practice.”

Assistant Director Bryan Vorndran of the FBI’s Cyber Division said threat actors affiliated with the People’s Republic of China (PRC) have targeted commercial telecommunications providers to compromise sensitive data and engage in cyber espionage.

“Together with our interagency partners, the FBI issued guidance to enhance the visibility of network defenders and to harden devices against PRC exploitation," Vorndran said.

"We strongly encourage organisations to review and implement the recommended measures in this guide and to report suspicious activity to their local FBI field office.”