TROJ_FAKEAV.BWT

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It poses as an antispyware application that uses pop-up messages displayed on the System Tray to make users think that their systems are infected. This tricks users to purchase the complete version of the said application. It poses as an antispyware application that displays deceptive warnings and misleading scan results. It may also add other applications which it detects upon its installation. It displays fake alerts that warn users of infection. It also displays fake scanning results of the affected system. It then asks for users to purchase it once scanning is completed. If users decide to purchase the rogue product, users are directed to a certain website asking for sensitive information, such as credit card numbers.

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan drops the following files:

• %System Root%\Documents and Settings\All Users\Start Menu\Programs\Startup\autorun.exe - also detected as TROJ_FAKEAV.BWT
• %User Profile%\Application Data\printer.exe - also detected as TROJ_FAKEAV.BWT
• %User Startup%\findfast.exe - also detected as TROJ_FAKEAV.BWT
• %Windows%\shell.exe - also detected as TROJ_FAKEAV.BWT
• %System%\printer.exe - also detected as TROJ_FAKEAV.BWT
• %System%\spoolvs.exe - also detected as TROJ_FAKEAV.BWT
• %User Temp%\5.bat
• %User Temp%\6.bat
• %System%\drivers\etc\st.im
• %Program Files%\altcmd\altcmd.inf
• %Program Files%\altcmd\altcmd32.dll
• %Program Files%\altcmd\uninstall.bat
• %System%\wowfx.dll
• %System%\npad.exe

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.. %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.. %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.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.. %Program Files% is the default Program Files folder, usually C:\Program Files.)

It drops the following copies of itself into the affected system:

• %System%\{malware file name}.exe

(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 creates the following folders:

• %System%\append.dll
• %System%\xlib254.dll
• %Program Files%\altcmd

(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.. %Program Files% is the default Program Files folder, usually C:\Program Files.)

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Spoolsv = "%System%\spoolvs.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Printer = "%System%\printer.exe"

It modifies the following registry entries to ensure it automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Shell = Explorer.exe %WINDOWS%\shell.exe

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

Other System Modifications

This Trojan adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
altcompare

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{2A8D06B4-1B40-009F-E531-629A59080F43}

It adds the following registry entries as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
system
DisableRegistryTools = 1

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
system
DisableTaskMgr = 1

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
ShowedCheckBrowser = Yes

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Check_Associations = No

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Enable Browser Extensions = yes

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
EnableBalloonTips = 1

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer
NoControlPanel = 1

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\Windows Update
NoAutoUpdate = 1

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\Windows Update
NoWindowsUpdate = 1

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Windows\WindowsUpdate\
AU
AutoUpdate = 0

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{2A8D06B4-1B40-009F-E531-629A59080F43}\InprocServer32
@ = %Program Files%\altcmd\altcmd32.dll

It creates the following registry entry(ies) to bypass Windows Firewall:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile\AuthorizedApplications\
List
%User Profile%\Application Data\printer.exe = %User Profile%\Application Data\printer.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile\AuthorizedApplications\
List
%System%\printer.exe = %System%\printer.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile\AuthorizedApplications\
List
%System%\spoolvs.exe = "%System%\spoolvs.exe:*:Enabled:@xpsp2res.dll,-22019"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile\AuthorizedApplications\
List
%Windows%\shell.exe = %Windows%\shell.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile\AuthorizedApplications\
List
%User Startup%\findfast.exe = %User Startup%\findfast.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile\AuthorizedApplications\
List
%System Root%\Documents and Settings\All Users\Start Menu\Programs\Startup\autorun.exe = %System Root%\Documents and Settings\All Users\Start Menu\Programs\Startup\autorun.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile\AuthorizedApplications\
List
%Windows%\system32\winav.exe = %Windows%\system32\winav.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%User Profile%\Application Data\printer.exe = %User Profile%\Application Data\printer.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System%\printer.exe = "%System%\printer.exe:*:Enabled:@xpsp2res.dll,-22019"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System%\spoolvs.exe = "%System%\spoolvs.exe:*:Enabled:@xpsp2res.dll,-22019"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%Windows%\shell.exe = %Windows%\shell.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%User Startup%\findfast.exe = %User Startup%\findfast.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%System Root%\Documents and Settings\All Users\Start Menu\Programs\Startup\autorun.exe = %System Root%\Documents and Settings\All Users\Start Menu\Programs\Startup\autorun.exe:*:Enabled:@xpsp2res.dll,-22019

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%Windows%\system32\winav.exe = %Windows%\system32\winav.exe:*:Enabled:@xpsp2res.dll,-22019

Rogue Antivirus Routine

This Trojan poses as an antispyware application that uses pop-up messages on the System Tray to make users think that their systems are infected. This tricks users to purchase the complete version of the said application.

It poses as an antispyware application that displays deceptive warnings and misleading scan results. It may also add other applications which it detects upon its installation.

It displays fake alerts that warn users of infection. It also displays fake scanning results of the affected system. It then asks for users to purchase it once scanning is completed. If users decide to purchase the rogue product, users are directed to a certain website asking for sensitive information, such as credit card numbers.