Backdoor:W32/Agent.IFX

Classification

Category :

Malware

Type :

Backdoor

Aliases :

Trojan.Win32.Agent.aulk, Sus/Dropper-A (Sophos), Backdoor:Win32/Koutodoor.A (Microsoft), Generic Backdoor Trojan (McAfee)

Summary

A remote administration tool (RAT) that bypasses the security features of a program, computer or network to give unauthorized access or control to its user.

Removal

Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note: You need administrative rights to change the settings.

Technical Details

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