Summary
The Cybersecurity and Infrastructure Security Agency (CISA) is aware of ongoing intrusions by People’s Republic of China (PRC) state-sponsored cyber actors using BRICKSTORM malware for long-term persistence on victim systems. BRICKSTORM is a sophisticated backdoor for VMware vSphere 1 , 2 and Windows environments. 3 Victim organizations are primarily in the Government Services and Facilities and Information Technology Sectors. BRICKSTORM enables cyber threat actors to maintain stealthy access and provides capabilities for initiation, persistence, and secure command and control. The malware employs advanced functionality, including multiple layers of encryption (e.g., HTTPS, WebSockets, and nested TLS), DNS-over-HTTPS (DoH) to conceal communications, and a SOCKS proxy to facilitate lateral movement and tunneling within victim networks. BRICKSTORM also incorporates long-term persistence mechanisms, such as a self-monitoring function that automatically reinstalls or restarts the malware if disrupted, ensuring its continued operation. In one confirmed compromise, PRC state-sponsored cyber actors accessed a web server inside the organization’s demilitarized zone (DMZ), moved laterally to an internal VMware vCenter server, then implanted BRICKSTORM malware.