Threat Group Cards: A Threat Actor Encyclopedia Archived: 2026-04-05 13:16:56 UTC Home > List all groups > List all tools > List all groups using tool Caterpillar Tool: Caterpillar Names Caterpillar Category Malware Type Reconnaissance, Backdoor, Info stealer, Downloader Description (ClearSky) Acting as a focal point, the group usually attacks webservers via a custom WebShell, namely Caterpillar – a variant of the open source WebShell ‘ASPXSpy’. By using WebShell, the attackers leave their fingerprint on the web server and the internal network, move laterally, and deploy additional tools. On each compromised network the attacker installed one or more WebShell, supposedly to gain persistence and diversify the use of similar tools. The attackers use the WebShell to communicate with their C&C server for running commands and exfiltrating sensitive information. Connection to the WebShell is made using NordVPN or ExpressVPN services. Information Last change to this tool card: 19 April 2021 Download this tool card in JSON format All groups using tool Caterpillar Changed Name Country Observed APT groups   Volatile Cedar 2012-Early 2020   1 group listed (1 APT, 0 other, 0 unknown) Source: https://apt.etda.or.th/cgi-bin/listgroups.cgi?u=608a396b-d841-425f-955c-4d1ee77d65e5 https://apt.etda.or.th/cgi-bin/listgroups.cgi?u=608a396b-d841-425f-955c-4d1ee77d65e5 Page 1 of 1