TROJ_DROPPR.MPS
TrojanDropper:Win32/Umrena.F (Microsoft); [00025a10.EXE]:Generic Dropper!1ej (McAfee); Trojan.Gen.2 (Symantec); Trojan-Downloader.Win32.Agent.tfzo (Kaspersky); Trojan.Win32.Generic.pak!cobra (Sunbelt); Trojan.Generic.6662246 (FSecure)
Windows 2000, Windows XP, Windows Server 2003
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.
TECHNICAL DETAILS
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:
- %Windows%\wscript32.exe
(Note: %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_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
wscript32 = "%Windows%\wscript32.exe hold09-14"
Other System Modifications
This Trojan adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0\
FLAGS
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0\
0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0\
0\win32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0\
HELPDIR
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}\ProxyStubClsid
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}\ProxyStubClsid32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}\TypeLib
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{75F73169-3459-40E0-A699-E63EC28147EC}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{75F73169-3459-40E0-A699-E63EC28147EC}\ProxyStubClsid
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{75F73169-3459-40E0-A699-E63EC28147EC}\ProxyStubClsid32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{75F73169-3459-40E0-A699-E63EC28147EC}\TypeLib
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
InprocServer32
HKEY_CLASSES_ROOT\wbhelper.wbtools
HKEY_CLASSES_ROOT\wbhelper.wbtools\Clsid
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
ProgID
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
Version
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
TypeLib
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
MiscStatus
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
MiscStatus\1
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
ToolboxBitmap32
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
Control
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
Verb
HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\
Verb\0
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}\TypeLib
Version = "1.0"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{75F73169-3459-40E0-A699-E63EC28147EC}\TypeLib
Version = "1.0"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\InprocServer32
ThreadingModel = "Apartment"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Enable = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Size = "a"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
InitHits = "64"
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\International\CpMRU
Factor = "14"
It modifies the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\0
1601 = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\1
1601 = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\2
1601 = "0"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\3
1601 = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\4
1601 = "0"
(Note: The default value data of the said registry entry is 1.)
It deletes the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
User Agent\Post Platform
Dropping Routine
This Trojan drops the following files:
- %Windows%\wbhelper.ocx
- %User Profile%\localprofile.vbs
(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.)
This report is generated via an automated analysis system.
SOLUTION
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
Restart in Safe Mode
Step 3
Delete this registry key
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\Classes\TypeLib
- {B58ED2B9-9069-43A7-97B6-B1D239C875CD}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}
- 1.0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0
- FLAGS
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0
- 0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0\0
- win32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{B58ED2B9-9069-43A7-97B6-B1D239C875CD}\1.0
- HELPDIR
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface
- {B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}
- ProxyStubClsid
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}
- ProxyStubClsid32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}
- TypeLib
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface
- {75F73169-3459-40E0-A699-E63EC28147EC}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{75F73169-3459-40E0-A699-E63EC28147EC}
- ProxyStubClsid
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{75F73169-3459-40E0-A699-E63EC28147EC}
- ProxyStubClsid32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{75F73169-3459-40E0-A699-E63EC28147EC}
- TypeLib
- In HKEY_CLASSES_ROOT\CLSID
- {30D3C5D0-AB43-4169-8381-B225058083A7}
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
- InprocServer32
- In HKEY_CLASSES_ROOT
- wbhelper.wbtools
- In HKEY_CLASSES_ROOT\wbhelper.wbtools
- Clsid
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
- ProgID
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
- Version
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
- TypeLib
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
- MiscStatus
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\MiscStatus
- 1
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
- ToolboxBitmap32
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
- Control
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}
- Verb
- In HKEY_CLASSES_ROOT\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\Verb
- 0
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International
- CpMRU
Step 4
Delete this registry value
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
- wscript32 = "%Windows%\wscript32.exe hold09-14"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{B2EC114F-6A65-4D63-815A-FFBA0C2F6E57}\TypeLib
- Version = "1.0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{75F73169-3459-40E0-A699-E63EC28147EC}\TypeLib
- Version = "1.0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{30D3C5D0-AB43-4169-8381-B225058083A7}\InprocServer32
- ThreadingModel = "Apartment"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
- Enable = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
- Size = "a"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
- InitHits = "64"
- In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\International\CpMRU
- Factor = "14"
Step 5
Restore this modified registry value
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\Internet Settings\Zones\0
- 1601 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1
- 1601 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2
- 1601 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
- From: 1601 = "0"
To: 1601 = ""1""
- From: 1601 = "0"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4
- From: 1601 = "0"
To: 1601 = ""1""
- From: 1601 = "0"
Step 6
Search and delete these files
- %Windows%\wbhelper.ocx
- %User Profile%\localprofile.vbs
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_DROPPR.MPS. 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.
Step 8
Restore these deleted registry keys/values from backup
*Note: Only Microsoft-related keys/values will be restored. If the malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\User Agent
- Post Platform
Did this description help? Tell us how we did.