TROJ_DLOAD.YU


 PLATFORM:

Windows 98, ME, NT, 2000, XP, Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


This Trojan adds registry entries to enable its automatic execution at every system startup.



  TECHNICAL DETAILS

File Size:

501248 bytes

Memory Resident:

Yes

Initial Samples Received Date:

05 Jan 2010


Installation


This Trojan drops the following file(s)/component(s):

  • %Program Files%\ANTIVIIRUS.EXE
  • %Program Files%\bho.exe
  • %Program Files%\tmp0.exe
  • %Program Files%\tmp1.exe
  • %Program Files%\tmp2.exe
  • %System%\778670\778670.dll
  • %Windows%\RESOURCES\SERVICERAM.DLL
  • C:\42356d3.bat
  • C:\z3g45.bat

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



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
antiviirus = "%Program Files%\antiviirus.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Run
DelayLoad = "{malware path and filename}"


It registers as a BHO to ensure its automatic execution every time Internet Explorer is used by adding the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Explorer\
Browser Helper Objects\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}
(default) =  



Other System Modifications


This Trojan adds the following registry keys:

HKEY_CLASSES_ROOT\CLSID\ {11192f33-32f2-47c2-97e0-7545830085d6}\
InprocServer32
(Default) = "%Windows%\Resources\ServiceRam.dll"

HKEY_CLASSES_ROOT\CLSID\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}
(Default) = "778670 Class"

HKEY_CLASSES_ROOT\CLSID\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\
InprocServer32
(Default) = "%System%\778670\778670.dll"

HKEY_CLASSES_ROOT\CLSID\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\
InprocServer32
ThreadingModel = "Apartment"

HKEY_CLASSES_ROOT\CLSID\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\
ProgID
(Default) = "f406.f406mgr.1"

HKEY_CLASSES_ROOT\CLSID\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\
TypeLib
(Default) = "{E63648F7-3933-440E-AAAA-A8584DD7B7EB}"

HKEY_CLASSES_ROOT\CLSID\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\
VersionIndependentProgID
(Default) = "f406.f406mgr"

HKEY_CLASSES_ROOT\f406.f406mgr
(Default) = "778670 Class"

HKEY_CLASSES_ROOT\f406.f406mgr.1
(default) = "778670 Class"

HKEY_CLASSES_ROOT\f406.f406mgr.1\CLSID
(default) = "{1B12F639-CBA9-45DD-89FE-9FA7D4340716}"

HKEY_CLASSES_ROOT\f406.f406mgr\CLSID
(default) = "{1B12F639-CBA9-45DD-89FE-9FA7D4340716}"

HKEY_CLASSES_ROOT\f406.f406mgr\CurVer
(default) = "f406.f406mgr.1"

HKEY_CLASSES_ROOT\Interface\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}
(default) = "Ie405mgr"

HKEY_CLASSES_ROOT\Interface\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}\
ProxyStubClsid
(default) = "{00020424-0000-0000-C000-000000000046}"

HKEY_CLASSES_ROOT\Interface\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}\
ProxyStubClsid32
(default) = "{00020424-0000-0000-C000-000000000046}"

HKEY_CLASSES_ROOT\Interface\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}\
TypeLib
(default) = "{E63648F7-3933-440E-B4F6-A8584DD7B7EB}"

HKEY_CLASSES_ROOT\Interface\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}\
TypeLib
(default) = "1.0"

HKEY_CLASSES_ROOT\TypeLib\ {E63648F7-3933-440E-B4F6-A8584DD7B7EB}\
1.0
(default) = "778670 1.0 Type Library"

HKEY_CLASSES_ROOT\TypeLib\ {E63648F7-3933-440E-B4F6-A8584DD7B7EB}\
1.0\0\win32
(default) = "%System%\778670\778670.dll"

HKEY_CLASSES_ROOT\TypeLib\ {E63648F7-3933-440E-B4F6-A8584DD7B7EB}\
1.0\FLAGS
(default) = "0"

HKEY_CLASSES_ROOT\TypeLib\ {E63648F7-3933-440E-B4F6-A8584DD7B7EB}\
1.0\HELPDIR
(default) = "%System%\778670\"

HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION
Logon = "4af13add"

HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Explorer\
Browser Helper Objects\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}
(default) = "778670 helper"

HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Explorer\
Browser Helper Objects\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}
NoExplorer = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\ShellServiceObjectDelayLoad
ServiceRam = "{11192f33-32f2-47c2-97e0-7545830085d6}"


  SOLUTION

Minimum Scan Engine:

8.900

VSAPI OPR PATTERN File:

6.857.00

VSAPI OPR PATTERN Date:

18 Feb 2010


Step 1


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\\CURRENTVERSION\\Run
    • antiviirus =%Program Files%\\antiviirus.exe
  • In HKEY_LOCAL_MACHINE\\SOFTWARE\\MICROSOFT\\ Windows\\CURRENTVERSION\\Run
    • DelayLoad ={malware path and filename}
  • In HKEY_CLASSES_ROOT\\CLSID\\ {11192f33-32f2-47c2-97e0-7545830085d6}\\ InprocServer32
    • (Default)=%Windows%\\Resources\\ServiceRam.dll
  • In HKEY_CLASSES_ROOT\\CLSID\\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}
    • (Default) =778670 Class
  • In HKEY_CLASSES_ROOT\\CLSID\\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\\ InprocServer32
    • (Default) =%System%\\778670\\778670.dll
  • In HKEY_CLASSES_ROOT\\CLSID\\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\\ InprocServer32
    • ThreadingModel =Apartment
  • In HKEY_CLASSES_ROOT\\CLSID\\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\\ ProgID
    • (Default)= f406.f406mgr.1
  • In HKEY_CLASSES_ROOT\\CLSID\\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\\ TypeLib
    • (Default)={E63648F7-3933-440E-AAAA-A8584DD7B7EB}
  • In HKEY_CLASSES_ROOT\\CLSID\\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}\\ VersionIndependentProgID
    • (Default) = f406.f406mgr
  • In HKEY_CLASSES_ROOT\\f406.f406mgr
    • (Default) =778670 Class
  • In HKEY_CLASSES_ROOT\\f406.f406mgr.1
    • (default)=778670 Class
  • In HKEY_CLASSES_ROOT\\f406.f406mgr.1\\CLSID
    • (default)={1B12F639-CBA9-45DD-89FE-9FA7D4340716}
  • In HKEY_CLASSES_ROOT\\f406.f406mgr\\CLSID
    • (default)={1B12F639-CBA9-45DD-89FE-9FA7D4340716}
  • In HKEY_CLASSES_ROOT\\f406.f406mgr\\CurVer
    • (default)=f406.f406mgr.1
  • In HKEY_CLASSES_ROOT\\Interface\\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}
    • (default)=Ie405mgr
  • In HKEY_CLASSES_ROOT\\Interface\\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}\\ ProxyStubClsid
    • (default)={00020424-0000-0000-C000-000000000046}
  • In HKEY_CLASSES_ROOT\\Interface\\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}\\ ProxyStubClsid32
    • (default)={00020424-0000-0000-C000-000000000046}
  • In HKEY_CLASSES_ROOT\\Interface\\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}\\ TypeLib
    • (default)={E63648F7-3933-440E-B4F6-A8584DD7B7EB}
  • In HKEY_CLASSES_ROOT\\Interface\\ {F7D09218-46D7-4D3D-9B7F-315204CD0836}\\ TypeLib
    • (default)=1.0
  • In HKEY_CLASSES_ROOT\\TypeLib\\ {E63648F7-3933-440E-B4F6-A8584DD7B7EB}\\ 1.0
    • (default)=778670 1.0 Type Library
  • In HKEY_CLASSES_ROOT\\TypeLib\\ {E63648F7-3933-440E-B4F6-A8584DD7B7EB}\\ 1.0\\0\\win32
    • (default)=%System%\\778670\\778670.dll
  • In HKEY_CLASSES_ROOT\\TypeLib\\ {E63648F7-3933-440E-B4F6-A8584DD7B7EB}\\ 1.0\\FLAGS
    • (default)=0
  • In HKEY_CLASSES_ROOT\\TypeLib\\ {E63648F7-3933-440E-B4F6-A8584DD7B7EB}\\ 1.0\\HELPDIR
    • (default)=%System%\\778670\\
  • In HKEY_LOCAL_MACHINE\\SOFTWARE\\MICROSOFT\\ Windows\\CURRENTVERSION
    • Logon=4af13add
  • In HKEY_LOCAL_MACHINE\\SOFTWARE\\MICROSOFT\\ Windows\\CURRENTVERSION\\Explorer\\ Browser Helper bjects\\{1B12F639-CBA9-45DD-89FE-9FA7D4340716}
    • (default)=778670 helper
  • In HKEY_LOCAL_MACHINE\\SOFTWARE\\MICROSOFT\\ Windows\\CURRENTVERSION\\Explorer\\ Browser Helper Objects\\ {1B12F639-CBA9-45DD-89FE-9FA7D4340716}
    • NoExplorer =1
  • In HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\ Windows\\CurrentVersion\\ShellServiceObjectDelayLoad
    • ServiceRam={11192f33-32f2-47c2-97e0-7545830085d6}


Step 2


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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.

 
  • In HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\Windows\CURRENTVERSION\Explorer\Browser Helper Objects
    • {1B12F639-CBA9-45DD-89FE-9FA7D4340716}


Step 3


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.
  • %Program Files%\ANTIVIIRUS.EXE
  • %Program Files%\bho.exe
  • %Program Files%\tmp0.exe
  • %Program Files%\tmp1.exe
  • %Program Files%\tmp2.exe
  • %System%\778670\778670.dll
  • %Windows%\RESOURCES\SERVICERAM.DLL
  • C:\42356d3.bat
  • C:\z3g45.bat


Step 4


Scan your computer with your Trend Micro product to delete files detected as TROJ_DLOAD.YU 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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