Trojan-Downloader:W32/Injecter.GX

Classification

Type:Trojan-Downloader

Summary

Injecter.GX is a trojan-downloader. A trojan-downloader is usually a standalone program that attempts to silently download and run other files from remote Web and FTP sites.

Removal

Trojan-Downloader

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Technical Details

Injecter.GX attempts to downloads files from:

http://88.255.[Removed]/e521.gif
http://88.255.[Removed]/e514.gif
http://88.255.[Removed]/e509.gif

It drops the downloaded files to the following location:

%windir%\system32\cdmk.dll
%temp%\dm4.exe

Injecter.GX also drops a DLL file from itself to the default temp folder which uses a name of tmp2.tmp. The file appears to be the downloader component itself.The malware also creates a temp file called _vdmstmsnd_.dat.It also attempts to send out information by performing the following command:

HTTP GET http://85.255.[Removed]/count.php?u=346&e=521&r=1

It searches for a process named teatimer.exe. It will attempt to terminate the process if discovered.The malware uses a mutex named STDP117.To ensure that the malware starts with Windows, it copies the malware file to:

C:\Documents and Settings\All Users\Start Menu \Programs\Startup\msupd[number].exe

Note: [number] is random.The malware creates the following registry entries:

HKEY_LOCAL_MACHINE\Software\Microsoft\Internet Explorer\PUID UID = 6727150054040000de564349 (Seems to be some kind of hash of the victim's computer.) UID2 = trojan.exe (Filename of the malware on execution.)
HKEY_LOCAL_MACHINE\Software\Microsoft\Internet Explorer\PUID\set thPCvzSYyScLKSRaW3l3jquJRD382MNqz3P4yEfx = "mult" thPCvzSYyScLKSRaW3l3jquJRD382MNqzHb4yEfx = "mult"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control \Session Manager PendingFileRenameOperations =" \??\C:\Samples\trojan.exe.1 \??\C:\Documents and Settings\All Users\Start Menu\ Programs\Startup\msupd43616.exe"