Security researchers warned that a Trojan horse took unusual self-defense measures-installing anti-virus software to clear other malware from infected PCs.
Security researchers said the SpamThru Trojan Horse installed the AntiVirusforWinGate software on the infected PC. The pirated software can scan malicious code on the system-but can miss SpamThru files, then, the detected malicious code is deleted at the next startup of the PC. According to reports, a typical Trojan Horse usually only disables anti-virus software to prevent the anti-virus software from upgrading the virus feature library and clearing specific malicious code. SpamThru brings the Trojan horse to a new level, 10 minutes after the DLL file is downloaded, it starts scanning the system. According to experts, SpamThru also demonstrated other advanced technologies, including the use of P2P-style, but rather insightful IRC control commands. Even if the control server is shut down, as long as there is still a node under control, hackers can still use the new control server to publish new commands.