TROJ_FAKEAV.CWT

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 executes then deletes itself afterward.

It employs registry shell spawning by adding certain registry entries. This allows this malware to execute even when other applications are opened.

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 copies of itself into the affected system:

• %Application Data%\{Random File Name}.exe

(Note: %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.)

It executes then deletes itself afterward.

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
2181007054 = "%Application Data%\{Random File Name}.exe"

It employs registry shell spawning to ensure its execution when certain file types are accessed by adding the following entries:

HKEY_CLASSES_ROOT\exefile\shell\
open\command
(Default) = ""%Application Data%\{Random File Name}.exe" -a "%1" %*"

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

HKEY_CLASSES_ROOT\.exe\shell\
open\command
(Default) = ""%Application Data%\{Random File Name}.exe" -a "%1" %*"

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

Other System Modifications

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

HKEY_CURRENT_USER\Software\Microsoft\
GDIPlus
FontCachePath = "%Application Data%"

It modifies the following registry key(s)/entry(ies) as part of its installation routine:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess
Start = "4"

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

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

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile
EnableFirewall = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile
DoNotAllowExceptions = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile
DisableNotifications = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
EnableFirewall = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
DoNotAllowExceptions = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
DisableNotifications = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\DomainProfile
DoNotAllowExceptions = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
EnableFirewall = "0"

It deletes the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\wuauserv

Dropping Routine

This Trojan drops the following files:

• %Application Data%\2863206pw6y2g87e16v8omv7m765ba5t63nh60777n5p5pr
• %Application Data%\GDIPFONTCACHEV1.DAT
• %User Profile%\Templates\2863206pw6y2g87e16v8omv7m765ba5t63nh60777n5p5pr
• %System Root%\Documents and Settings\All Users\Application Data\2863206pw6y2g87e16v8omv7m765ba5t63nh60777n5p5pr
• %User Temp%\2863206pw6y2g87e16v8omv7m765ba5t63nh60777n5p5pr

(Note: %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.. %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.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %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.)

Other Details

This Trojan connects to the following possibly malicious URL:

• http://{BLOCKED}kawuhady.com/1126000112
• http://{BLOCKED}movom.com/1126000112
• http://{BLOCKED}zev.com/1126000112
• http://{BLOCKED}fotoqy.com/1126000112
• http://{BLOCKED}mici.com/1126000112
• http://{BLOCKED}zugyky.com/1126000112
• http://{BLOCKED}uzuxil.com/1126000112
• http://{BLOCKED}lali.com/1126000112
• http://{BLOCKED}oxyzum.com/1126000112
• http://{BLOCKED}nubyg.com/1126000112
• http://{BLOCKED}oxyzum.com/1126000112
• http://{BLOCKED}jige.com/1126000112