TROJ_NSIS.AD

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 deletes itself after execution.

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 creates the following folders:

• %System Root%\DOCUME~1
• %System Root%\DOCUME~1\Wilbert
• %User Profile%\LOCALS~1
• %User Temp%\nsa2.tmp
• %Program Files%\MainBoan
• %Start Menu%\Programs\¸ÞÀκ¸¾È

(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 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.. %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Profiles\{user name}\Start Menu on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu on Windows NT and C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003.)

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
MainBoan = "%Program Files%\MainBoan\MainBoan.exe /run1"

Other System Modifications

This Trojan deletes the following files:

• %User Temp%\nso1.tmp
• %User Temp%\nsa2.tmp
• %System Root%\DelUS.bat
• %Program Files%\MainBoan\ADDSCH~1.EXE
• %Program Files%\MainBoan\del.bat
• %Program Files%\MainBoan\ADDSCH~2.EXE
• %Program Files%\MainBoan\del_.bat

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

It adds the following registry keys:

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\App Paths\
MainBoan.exe

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Uninstall\
MainBoan

HKEY_LOCAL_MACHINE\Software\MainBoan

HKEY_LOCAL_MACHINE\Software\MainBoanPartner

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\jecomm

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
MainBoan
DisplayName = "¸ÞÀκ¸¾È"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
MainBoan
UninstallString = "%Program Files%\MainBoan\uninst.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
MainBoan
DisplayIcon = "%Program Files%\MainBoan\MainBoan.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
MainBoan
DisplayVersion = "1.000"

HKEY_LOCAL_MACHINE\SOFTWARE\MainBoan
pid = "command"

HKEY_LOCAL_MACHINE\SOFTWARE\MainBoan
InstallDate = "20120311"

HKEY_LOCAL_MACHINE\SOFTWARE\MainBoan
Version = "1.000"

HKEY_LOCAL_MACHINE\SOFTWARE\MainBoan
UpdateVersion = "1.000"

HKEY_LOCAL_MACHINE\SOFTWARE\MainBoanPartner
install = "install_check"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\jecomm
name = "MainBoan,"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\jecomm
MainBoan = "2012031117"

HKEY_LOCAL_MACHINE\SOFTWARE\MainBoan
restart = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\MainBoan
Environment = "11111111111111"

Dropping Routine

This Trojan drops the following files:

• %User Temp%\nsisos.dll
• %User Temp%\nsa2.tmp\System.dll
• %User Temp%\nsa2.tmp\SelfDelete.dll
• \DelUS.bat
• %Program Files%\MainBoan\MainBoan.exe
• %Start Menu%\Programs\¸ÞÀκ¸¾È\¸ÞÀκ¸¾È.lnk
• %Desktop%\¸ÞÀκ¸¾È.lnk
• %Program Files%\MainBoan\MainBoanMtr.exe
• %Program Files%\MainBoan\MainBoanuck.exe
• %Program Files%\MainBoan\AddScheduler.exe
• %Program Files%\MainBoan\AddScheduler_.exe
• %Start Menu%\Programs\¸ÞÀκ¸¾È\¸ÞÀκ¸¾È Á¦°Å.lnk
• %Program Files%\MainBoan\uninst.exe
• %User Temp%\nsa2.tmp\DLLWebCount.dll
• %User Temp%\nsa2.tmp\inetc.dll
• wdate.ini
• %Program Files%\MainBoan\MainBoan.xml
• del.bat
• %Program Files%\MainBoan\MainBoan_uninst.xml
• del_.bat
• %User Temp%\temp0.lnk

(Note: %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.. %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Profiles\{user name}\Start Menu on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu on Windows NT and C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003.. %Desktop% is the current user's desktop, which is usually C:\Windows\Profiles\{user name}\Desktop on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Desktop on Windows NT, and C:\Documents and Settings\{User Name}\Desktop on Windows 2000, XP, and Server 2003.)

Other Details

This Trojan connects to the following possibly malicious URL:

• http://{BLOCKED}an.com/apps/applog.php?kind=install&pid=command
• http://update.{BLOCKED}an.com/wdate.ini
• http://update.{BLOCKED}an.com/partner/partner_info.ini
• http://update.{BLOCKED}an.com/update_data.ini
• http://update.{BLOCKED}an.com/version.ini

It deletes itself after execution.

This report is generated via an automated analysis system.