TROJ_DROPR.OLG
Windows 2000, Windows XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
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
461,955 bytes
EXE
Yes
09 Jan 2014
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:
- %User Temp%\34cd9.tmp
(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, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)
Autostart Technique
This Trojan registers itself 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\{DAF9F01C-30F0-4A52-AF52-E236961977F4}
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\2944455d
HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Services\55ef70db
Other System Modifications
This Trojan deletes the following files:
- %User Profile%\Cookies\index.dat
- %System%\Drivers\EstRtw.sys
- %User Temp%\35082.exe
(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %System% is the Windows system folder, which is usually C:\Windows\System32.. %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, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)
It adds the following registry keys:
HKEY_CLASSES_ROOT\CLSID\HOOK_ID
HKEY_CLASSES_ROOT\CLSID\SYS_DLL
HKEY_CLASSES_ROOT\IEHelper.IEHlprObj.1
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
IEHelper.IEHlprObj.1\CLSID
HKEY_CLASSES_ROOT\IEHelper.IEHlprObj
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
IEHelper.IEHlprObj\CLSID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
IEHelper.IEHlprObj\CurVer
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}\ProgID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}\VersionIndependentProgID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}\Programmable
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}\InprocServer32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}\TypeLib
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0\
FLAGS
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0\
0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0\
0\win32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0\
HELPDIR
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}\ProxyStubClsid
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}\ProxyStubClsid32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}\TypeLib
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\HOOK_ID
name = "35082.exe"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\2944455d
Type = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\2944455d
ErrorControl = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\2944455d
Start = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\2944455d
ImagePath = "\??\%System%\drivers\2944455d.sys"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\SYS_DLL
name = "JDUYh84.dll"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\55ef70db
Type = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\55ef70db
ErrorControl = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\55ef70db
Start = "1"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\55ef70db
ImagePath = "\??\%System%\drivers\55ef70db.sys"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}\InprocServer32
ThreadingModel = "Apartment"
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}\TypeLib
Version = "1.0"
It deletes the following registry keys:
HKEY_CLASSES_ROOT\CLSID\TANG2_OTP
HKEY_CLASSES_ROOT\CLSID\HOK_OTP
HKEY_CLASSES_ROOT\CLSID\TANG1_NCP
HKEY_CLASSES_ROOT\CLSID\TANG1_URL
HKEY_CLASSES_ROOT\CLSID\AH3SEC
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects\{18DF081C-E8AD-4283-A596-FA578C2EBDC3}
HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Services\2944455d\Enum
HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Services\2944455d\Security
HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Services\55ef70db\Enum
HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Services\55ef70db\Security
Dropping Routine
This Trojan drops the following files:
- %User Temp%\35082.exe
- %System%\drivers\2944455d.sys
- %System%\verslon.dll
- %User Temp%\A1.zip
- %User Temp%\B1.zip
- %User Temp%\C1.zip
- %User Temp%\D1.zip
- %User Temp%\ujs.dll
- %User Temp%\JDUYh84.dll
- %System%\drivers\55ef70db.sys
- %System%\vorsion.dll
- %System%\version.dll
- %System%\midimap.dll
(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, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %System% is the Windows system folder, which is usually C:\Windows\System32.)
Other Details
This Trojan connects to the following possibly malicious URL:
- http://{BLOCKED}4.7.254/post.asp?{random characters}
It deletes itself after execution.
This report is generated via an automated analysis system.
SOLUTION
9.300
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 2
Restart in Safe Mode
Step 3
Close all opened browser windows
Step 4
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\System\CurrentControlSet\Services
- 2944455d
- In HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services
- 55ef70db
- In HKEY_CLASSES_ROOT\CLSID
- HOOK_ID
- In HKEY_CLASSES_ROOT\CLSID
- SYS_DLL
- In HKEY_CLASSES_ROOT
- IEHelper.IEHlprObj.1
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\IEHelper.IEHlprObj.1
- CLSID
- In HKEY_CLASSES_ROOT
- IEHelper.IEHlprObj
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\IEHelper.IEHlprObj
- CLSID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\IEHelper.IEHlprObj
- CurVer
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
- {DAF9F01C-30F0-4A52-AF52-E236961977F4}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}
- ProgID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}
- VersionIndependentProgID
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}
- Programmable
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}
- InprocServer32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}
- TypeLib
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer
- Browser Helper Objects
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib
- {D42047D9-38C2-4FD1-8337-F69C8F835A30}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}
- 1.0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0
- FLAGS
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0
- 0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0\0
- win32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{D42047D9-38C2-4FD1-8337-F69C8F835A30}\1.0
- HELPDIR
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface
- {C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}
- ProxyStubClsid
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}
- ProxyStubClsid32
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}
- TypeLib
Step 5
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_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\HOOK_ID
- name = "35082.exe"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\2944455d
- Type = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\2944455d
- ErrorControl = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\2944455d
- Start = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\2944455d
- ImagePath = "\??\%System%\drivers\2944455d.sys"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\SYS_DLL
- name = "JDUYh84.dll"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\55ef70db
- Type = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\55ef70db
- ErrorControl = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\55ef70db
- Start = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\55ef70db
- ImagePath = "\??\%System%\drivers\55ef70db.sys"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{DAF9F01C-30F0-4A52-AF52-E236961977F4}\InprocServer32
- ThreadingModel = "Apartment"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{C0BEBABF-1785-4075-8C4D-8FEE7833D3CD}\TypeLib
- Version = "1.0"
Step 6
Search and delete these components
- %User Temp%\35082.exe
- %System%\drivers\2944455d.sys
- %System%\verslon.dll
- %User Temp%\A1.zip
- %User Temp%\B1.zip
- %User Temp%\C1.zip
- %User Temp%\D1.zip
- %User Temp%\ujs.dll
- %User Temp%\JDUYh84.dll
- %System%\drivers\55ef70db.sys
- %System%\vorsion.dll
- %System%\version.dll
- %System%\midimap.dll
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_DROPR.OLG. 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 this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.
- %User Profile%\Cookies\index.dat
- %System%\Drivers\EstRtw.sys
- %User Temp%\35082.exe
Step 9
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_CLASSES_ROOT\CLSID
- TANG2_OTP
- In HKEY_CLASSES_ROOT\CLSID
- HOK_OTP
- In HKEY_CLASSES_ROOT\CLSID
- TANG1_NCP
- In HKEY_CLASSES_ROOT\CLSID
- TANG1_URL
- In HKEY_CLASSES_ROOT\CLSID
- AH3SEC
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects
- {18DF081C-E8AD-4283-A596-FA578C2EBDC3}
- In HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\2944455d
- Enum
- In HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\2944455d
- Security
- In HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\55ef70db
- Enum
- In HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\55ef70db
- Security
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