Chinese hacker group APT41 misuses Google Command and Control (GC2) tool for attacks
by Tina Siering
Image source: Google
Google experts warn that the state-sponsored Chinese hacking group APT41 is misusing the Google Command and Control (GC2) tool. Attacks on Taiwanese media companies and an unnamed Italian recruitment company are known. Google Command and Control is an open-source program written in the Go programming language that was developed to simulate attacks and is used in Red Teaming.
APT 41 (also known as HOODOO) is a Chinese state-sponsored hacking group known for attacking a variety of industries in the US, Asia and Europe. In the past, their activities have been found to overlap with those of other well-known Chinese hacker groups such as BARIUM and Winnti.
GC2 designed for red-team operations
Google Command and Control is designed to provide management and control during a Red Team operation that does not require any specific configuration (e.g. custom domain, VPS, CDN, etc.). The programme interacts exclusively with Google domains (*.google.com) to make it difficult to expose.
GC2 should only be used by legitimate security professionals and Red Teams, with the goal of identifying and fixing vulnerabilities in systems.
Mode of operation: GC2 is installed as an agent on compromised devices. It allows an attacker to execute commands via Google Sheet on the target machine and install, download additional payloads from Google Drive or exfiltrate stolen data into the cloud storage service.
GC2 abused for attacks - and foiled
Although it is not known what malware was distributed in these attacks, the APT41 group is known to install a variety of malware on compromised systems, including rootkits, bootkits, Winnti malware, backdoors, Cobalt Strike or point-of-sale malware, in short tools commonly used by Chinese hacker groups.
Switching to legitimate tools
The use of GC2 by APT41 is another indicator of the trend for hacker groups to use legitimate, freely available and open-source tools and remote monitoring and management (RMM) platforms in their attacks to make attribution more difficult.
One reason for this is that Cobalt Strike is becoming easier to spot in attack patterns.
Companies should therefore remain vigilant and ensure the necessary awareness and targeted monitoring of their environment. Test your detection strategies and response processes.