Agentdoc.c is a trojan that drops malicious files on the infected computer. Once executed, the parasite opens a Microsoft Word document written in Japanese or Chinese, and installs itself to the system. It also installs a rootkit and keylogger that logs all user keystrokes. Gathered data is stored locally on the compromised computer. Agentdoc.c uses a rootkit to hide its files and registry entries, and therefore avoid detection. The trojan also attempts to download from the Internet and execute other malicious files. It runs as a service on every Windows startup.