Backdoor:W32/Agent.IFX

This malware installs a DLL file to the system that provides backdoor functionality. The malware also makes changes to the Internet Explorer (IE) web browser start page and attempts to connect to remote sites.

Installation

During installation, the malware creates these files:

• %appdata%\Microsoft\Internet Explorer\Quick Launch\Internet Explorer.lnk - Creates a quicklaunch IE, opens www.6700.cn
• %favorites%\.url - Creates a "favorites" link in IE to the page www.6700.cn
• %windir%\system32\[RANDOM].dll
• %windir%\system32\drivers\[RANDOM].sys
• %windir%\system32\[RANDOM].bat

It also changes the IE start page to:

• HK_USERS\[...]\Microsoft\Internet Explorer\Main Start Page = "www.6700.cn?tn=1027271"

Execution

When first executed, the malware will create the files listed above. It will then execute the batch file to delete itself.The DLL file and driver are also installed into the system. From then on, the DLL and driver will provide the backdoor functionality.The malware attempts to connect to:

• www. buyaohenchang. cn/api.php?xxxxxxx
• www. woyaochidongxi. com/update.php?xxxxx

Registry

The malware will launch itself by adding this entry into registry :

• HKLM\System\CurrentControlSet\Services\[RANDOM] ImagePath = system32\drivers\[RANDOM].sys