ALIASES:

Worm:Win32/Lightmoon.H (Microsoft); W32/MoonLight.worm (McAfee); W32.Rontokbro@mm (Symantec); Worm.Win32.Moonlight.gen (v) (Sunbelt)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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

It disables Task Manager, Registry Editor, and Folder Options.

  TECHNICAL DETAILS

File Size: 141,312 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 16 Oct 2012

Arrival Details

This worm 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 worm drops the following copies of itself into the affected system:

  • %User Profile%\O71710Z\service.exe

(Note: %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.)

It creates the following folders:

  • %Windows%\M25053
  • %User Profile%\Templates\O71710Z
  • %System%\X57785go

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.. %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% 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 worm adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
T1TT4 = "\l.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
T = "\sa-.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, \Tux.exe"

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Userinit = "\userinit.exe , \JabLay.com"

(Note: The default value data of the said registry entry is %Windows%\system32\userinit.exe,.)

Other System Modifications

This worm adds the following registry keys:

HKEY_CURRENT_USER\Software\VB and VBA Program Settings\
untukmu\version

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
msconfig.exe

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
regedit.exe

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\Path

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\biang

It adds the following registry entries:

HKEY_CURRENT_USER\Software\VB and VBA Program Settings\
untukmu\version
me = "4"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
msconfig.exe
debugger = "\notepad.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
regedit.exe
debugger = "\notepad.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\Path
1 = "M25053"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\Path
2 = "O71710Z"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\Path
3 = "X57785go"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\biang
1 = "9927a"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\biang
2 = "184c"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\biang
3 = "c454d"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\biang
4 = "3536"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
TUX\biang
5 = "36d24"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
CabinetState
FullPath = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
HideFileExt = "1"

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
Hidden = "0"

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

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess
Start = "0"

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
User Shell Folders
Common Startup = "0"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\SuperHidden
UncheckedValue = "0"

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

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\SafeBoot
AlternateShell = "l.exe"

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

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\
Control\SafeBoot
AlternateShell = "l.exe"

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

It creates the following registry entry(ies) to disable Task Manager, Registry Tools and Folder Options:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableRegistryTools = "1"

Dropping Routine

This worm drops the following files:

  • \msvbvm60.dll
  • %System%\msvbvm60.dll
  • %User Profile%\O71710Z\winlogon.exe
  • %Windows%\M25053\EmangEloh.exe
  • %Windows%\M25053\smss.exe
  • %System%\X57785go\Z627322cie.cmd
  • %Windows%\sa-006220.exe
  • %Windows%\Ti804173ta.exe
  • %Windows%\M25053\Ja013622bLay.com
  • %System%\627322804173l.exe
  • %User Startup%\sql.cmd
  • %User Profile%\O71710Z\TuxO71710Z.exe

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.200

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Identify and delete files detected as WORM_MOONLIGH.AH using either the Startup Disk or Recovery Console

[ Learn More ]

Step 3

Enable Registry Editor, Task Manager, and Folder options

[ Learn More ]
By doing this step, you also enable other applications/programs disabled by this malware/grayware.

Step 4

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\VB and VBA Program Settings\untukmu
    • version
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies
    • System
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options
    • msconfig.exe
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options
    • regedit.exe
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX
    • Path
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX
    • biang

Step 5

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • T1TT4 = "\l.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • T = "\sa-.exe"
  • In HKEY_CURRENT_USER\Software\VB and VBA Program Settings\untukmu\version
    • me = "4"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • ShowSuperHidden = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\msconfig.exe
    • debugger = "\notepad.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\regedit.exe
    • debugger = "\notepad.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX\Path
    • 1 = "M25053"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX\Path
    • 2 = "O71710Z"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX\Path
    • 3 = "X57785go"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX\biang
    • 1 = "9927a"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX\biang
    • 2 = "184c"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX\biang
    • 3 = "c454d"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX\biang
    • 4 = "3536"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\TUX\biang
    • 5 = "36d24"

Step 6

Restore this modified registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\CabinetState
    • FullPath = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • From: HideFileExt = "1"
      To: HideFileExt = ""1""
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • From: Hidden = "0"
      To: Hidden = ""2""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess
    • From: Start = "0"
      To: Start = ""2""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders
    • From: Common Startup = "0"
      To: Common Startup = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\SuperHidden
    • From: UncheckedValue = "0"
      To: UncheckedValue = ""1""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\SafeBoot
    • From: AlternateShell = "l.exe"
      To: AlternateShell = ""cmd.exe""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\Control\SafeBoot
    • From: AlternateShell = "l.exe"
      To: AlternateShell = ""cmd.exe""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
    • From: Shell = "explorer.exe, \Tux.exe"
      To: Shell = ""Explorer.exe""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
    • From: Userinit = "\userinit.exe , \JabLay.com"
      To: Userinit = ""%Windows%\system32\userinit.exe,""

Step 7

Search and delete these files

[ Learn More ]
There may be some component files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • \msvbvm60.dll
  • %System%\msvbvm60.dll
  • %User Profile%\O71710Z\winlogon.exe
  • %Windows%\M25053\EmangEloh.exe
  • %Windows%\M25053\smss.exe
  • %System%\X57785go\Z627322cie.cmd
  • %Windows%\sa-006220.exe
  • %Windows%\Ti804173ta.exe
  • %Windows%\M25053\Ja013622bLay.com
  • %System%\627322804173l.exe
  • %User Startup%\sql.cmd
  • %User Profile%\O71710Z\TuxO71710Z.exe

Step 8

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %Windows%\M25053
  • %User Profile%\Templates\O71710Z
  • %System%\X57785go

Step 9

Scan your computer with your Trend Micro product to delete files detected as WORM_MOONLIGH.AH. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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