ALIASES:

Trojan:Win32/Matsnu.gen!A (Microsoft); Generic BackDoor.u (McAfee); Backdoor.Matsnu (Symantec); Trojan-Dropper.Win32.Injector.cvqz (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan:W32/Agent.DTSY (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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.

  TECHNICAL DETAILS

File Size: 112,640 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 18 Apr 2012

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:

  • %Program Files%\Trusteer\Rapport\bin
  • %Program Files%\Trusteer
  • %Program Files%\Trusteer\Rapport

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

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
userinit = "%System%\userinit.exe,%System%\9DA2DC20F0BDFF95A457.exe,"

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

It registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\RapportMgmtService

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\RapportCerberus_29574

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\RapportEI

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\RapportKELL

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\RapportPG

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CLASSES_ROOT\.eze

HKEY_CLASSES_ROOT\MyEze.1\shell\
open\command

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
RapportSetup-Full.exe

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
RapportSetup.exe

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
RapportMgmtService.exe

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
RapportService.exe

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
RapportSetup-Full.exe
Debugger = "RPXService.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
RapportSetup.exe
Debugger = "RPXService.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
RapportMgmtService.exe
Debugger = "RPService.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
RapportService.exe
Debugger = "RPService.exe"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Windows
load = "%User Temp%\392D0E8CF0BDFF9556C7.exe,"

Dropping Routine

This Trojan drops the following files:

  • %System%\9DA2DC20F0BDFF95A457.exe
  • %User Temp%\392D0E8CF0BDFF9556C7.exe
  • %Windows%\RPService.exe
  • %Program Files%\Trusteer\Rapport\bin\RapportService.exe
  • %Start Menu%\Programs\Trusteer Rapport\Rapport Console.lnk
  • %Start Menu%\Programs\Trusteer Rapport\Start Rapport.lnk
  • %Start Menu%\Programs\Trusteer Rapport\Stop Rapport.lnk

(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.. %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.. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.. %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.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}.94.165/asdfasdgfs/Fiur5sDzx2col.php?id=F0BDFF95414952426441&stat=0

It deletes itself after execution.

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 TROJ_DROPPR.FH using either the Startup Disk or Recovery Console

[ Learn More ]

Step 3

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_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • RapportMgmtService
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • RapportCerberus_29574
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • RapportEI
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • RapportKELL
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • RapportPG
  • In HKEY_CLASSES_ROOT
    • .eze
  • In HKEY_CLASSES_ROOT\MyEze.1\shell\open
    • command
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Image File Execution Options
    • RapportSetup-Full.exe
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Image File Execution Options
    • RapportSetup.exe
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Image File Execution Options
    • RapportMgmtService.exe
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Image File Execution Options
    • RapportService.exe

Step 4

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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\RapportSetup-Full.exe
    • Debugger = "RPXService.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\RapportSetup.exe
    • Debugger = "RPXService.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\RapportMgmtService.exe
    • Debugger = "RPService.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\RapportService.exe
    • Debugger = "RPService.exe"

Step 5

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 NT\CurrentVersion\Windows
    • load = "%User Temp%\392D0E8CF0BDFF9556C7.exe,"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
    • From: userinit = "%System%\userinit.exe,%System%\9DA2DC20F0BDFF95A457.exe,"
      To: userinit = ""%Windows%\system32\userinit.exe,""

Step 6

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.
  • %System%\9DA2DC20F0BDFF95A457.exe
  • %User Temp%\392D0E8CF0BDFF9556C7.exe
  • %Windows%\RPService.exe
  • %Program Files%\Trusteer\Rapport\bin\RapportService.exe
  • %Start Menu%\Programs\Trusteer Rapport\Rapport Console.lnk
  • %Start Menu%\Programs\Trusteer Rapport\Start Rapport.lnk
  • %Start Menu%\Programs\Trusteer Rapport\Stop Rapport.lnk

Step 7

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.
  • %Program Files%\Trusteer\Rapport\bin
  • %Program Files%\Trusteer
  • %Program Files%\Trusteer\Rapport

Step 8

Scan your computer with your Trend Micro product to delete files detected as TROJ_DROPPR.FH. 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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