Trojan-Dropper:W32/Ambler.D

Classification

Type:Trojan-Dropper

Trojan-Dropper:W32/Ambler.D, Trojan-Dropper:W32/Ambler.D, Trojan-Dropper.Win32.Agent.absn, TrojanDropper:Win32/Ambler.A (Microsoft)

Summary

This type of trojan contains one or more malicious programs, which it will secretly install and execute.

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 drops a malicious file that steals credentials from Internet banking websites.

Installation

The following component is injected into the iexplorer.exe process:

%windir%\system32\svchstb.dll

The injected code is registered as an Internet Explorer Browser Helper Object (BHO). This injected code is the main component file that allows the malware to steal passwords from Internet Explorer's auto-complete passwords cache.The malware also attempts to connect to a remote server and download files:

http://vcounter.cn/[...]/cd.php?userid=[random_number]

File System Changes

Creates these files:

%windir%\system32\edl.dat
%windir%\system32\svchstb.dll
%windir%\system32\bb1.dat
%windir%\system32\rc.dat
%windir%\system32\ps1.dat
%windir%\system32\alog.txt

Modified these files:

%windir%\system32\alog.txt

Registry Modifications

Sets these values:

[HKLM\Software\MRSoft] LN = X]HCX_IOGG
[HKLM\Software\MRSoft] CODIGO = lVUVST' T:...':#'"v:VV%#:%T%'.U"'VR .j
[HKLM\Software\Classes\CLSID\{ABADC07C-9990-405a-AA24-2C209B50AE79}] @ = Rmn plugin
[HKLM\Software\Classes\CLSID\{ABADC07C-9990-405a-AA24-2C209B50AE79}\TypeLib] @ = {0017825A-A697-488f-84AA-b7CEE2A02333}
[HKLM\Software\Classes\CLSID\{ABADC07C-9990-405a-AA24-2C209B50AE79}\ProgID] @ = RITLAB.1
[HKLM\Software\Classes\CLSID\{ABADC07C-9990-405a-AA24-2C209B50AE79}\InprocServer32] @ = svchstb.dll
[HKLM\Software\MRSoft\P] N = [random_number]
[HKCU\Software\Microsoft\Internet Explorer\Main] Enable Browser Extensions = yes

Creates these keys:

HKLM\Software\MRSoft
HKLM\Software\MRSoft\P
HKLM\Software\Classes\CLSID\{ABADC07C-9990-405a-AA24-2C209B50AE79}
HKLM\Software\Classes\CLSID\{ABADC07C-9990-405a-AA24-2C209B50AE79}\InprocServer32
HKLM\Software\Classes\CLSID\{ABADC07C-9990-405a-AA24-2C209B50AE79}\ProgID
HKLM\Software\Classes\CLSID\{ABADC07C-9990-405a-AA24-2C209B50AE79}\TypeLib
HKLM\Software\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects\{ABADC07C-9990-405a-AA24-2C209B50AE79}
HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\{ABADC07C-9990-405A-AA24-2C209B50AE79}
HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\{ABADC07C-9990-405A-AA24-2C209B50AE79}\iexplore