PRC State-Sponsored Use of BRICKSTORM Malware for Persistent Access

People’s Republic of China (PRC) state-sponsored cyber actors have been observed deploying the sophisticated BRICKSTORM backdoor malware to maintain long-term, stealthy access within government and information technology sector networks. BRICKSTORM targets both VMware vSphere and Windows environments, employing advanced evasion techniques such as multiple layers of encryption, DNS-over-HTTPS, and a SOCKS proxy for lateral movement. The malware is designed for persistence, with self-monitoring features that allow it to automatically reinstall or restart if disrupted, and has been linked to intrusions where attackers leveraged legitimate credentials and exfiltrated sensitive data from compromised systems.

CISA, NSA, and the Canadian Centre for Cyber Security have jointly released detailed analysis and detection guidance for BRICKSTORM, including indicators of compromise (IOCs), YARA and Sigma rules, and technical breakdowns of eight malware samples. Organizations in government and critical infrastructure sectors are urged to use these resources to detect and respond to BRICKSTORM infections, and to report any related activity to authorities. The campaign highlights the evolving capabilities of PRC state-sponsored actors and the need for robust monitoring and incident response in targeted sectors.