TROJ_OLMARIK.EFF

This Trojan modifies certain registry entries. It connects to certain URL(s) to download its component file(s). It saves the files it downloads using certain file names. Trend Micro detects the dowloaded file as RTKT_OLMARIK.EFF.

It displays a fake scan for Internet Security 2011. It connects to www.yahoo.com to check for an internet connection. It adds certain registry entries to add an uninstall option to the Control Panel. It also shows fake detections in the system and intercepts files when they are executed. This leads users into thinking that their system is infected by a bogus keylogger and will subsequently click on the "Remove Threat" button. It then directs users to a payment page where their banking credentials are required.

This Trojan may be downloaded by other malware/grayware/spyware from remote sites. It may be unknowingly downloaded by a user while visiting malicious websites.

It deletes itself after execution.

Arrival Details

This Trojan may be downloaded by other malware/grayware/spyware from remote sites.

It may be unknowingly downloaded by a user while visiting malicious websites.

Installation

This Trojan drops the following file(s)/component(s):

• %System%\exefile.exe - also detected as TROJ_OLMARIK.EFF
• %System%\us?rinit.exe - also detected as TROJ_OLMARIK.EFF

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

It drops the following non-malicious files:

• %Temp%\{E9C1E0AC-C9B1-4c85-94DE-9C1518918D01}.tlb
• %Temp%\{E9C1E0AC-C9B1-4c85-94DE-9C1518918D02}.tlb
• %Application Data%\.wtav
• %System%\ms{random characters}.dll

(Note: %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp or C:\WINNT\Temp.. %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.. %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

Autostart Technique

This Trojan registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\userinit
ImagePath = \.\globalroot\%System%\us?rinit.exe

Other System Modifications

This Trojan modifies the following registry entries:

HKEY_CLASSES_ROOT\exefile\shell\
open\command
(Default) = exefile /shell <%1> %*

(Note: The default value data of the said registry entry is %1 %*.)

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\wscsvc
Start = 4

(Note: The default value data of the said registry entry is 2.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
exefile\shell\open\
command
(Default) = exefile /shell <%1> %*

(Note: The default value data of the said registry entry is %1 %*.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
AntiVirusOverride = 1

(Note: The default value data of the said registry entry is 0.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
FirewallOverride = 1

(Note: The default value data of the said registry entry is 0.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
AntiSpywareOverride = 1

(Note: The default value data of the said registry entry is 0.)

Download Routine

This Trojan connects to the following URL(s) to download its component file(s):

• http://{BLOCKED}.{BLOCKED}.21.219:8083/ask?t={value}&u={value}&a={value}&m={value}&h={value}

It saves the files it downloads using the following names:

• %System%\drivers\vbma{random characters}.sys

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

Trend Micro detects the dowloaded file as:

• RTKT_OLMARIK.EFF

Other Details

This Trojan adds the following registry entries to add an uninstall option to the Control Panel:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
{random CLSID}
NoModify = 1

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
{random CLSID}
NoRepair = 1

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
{random CLSID}
DisplayName = Antivirus 2010

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
{random CLSID}
Publisher = WebTop Software Limited

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
{random CLSID}
URLInfoAbout = http://www.{BLOCKED}billing.com/

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
{random CLSID}
UninstallString = \.\globalroot\%System%\us?rinit.exe /uninstall

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
{random CLSID}
DisplayIcon = \.\globalroot\%System%\us?rinit.exe

It connects to the following URL(s) to check for an Internet connection:

• www.yahoo.com

It displays the following images:

It does the following:

• shows fake detections in the system and intercepts files when they are executed. Below are screenshots of the fake application when executed:
  
  
  
  
  
  This leads users into thinking that their system is infected by a bogus keylogger and will subsequently click on the "Remove Threat" button. It then directs users to a payment page where their banking credentials are required. Below is a screenshot of the said page:
  
  

It deletes itself after execution.