TROJ_BOHU.A
TrojanDropper:Win32/Bohu.A (Microsoft); Bohu.dr (McAfee); Trojan.Bohu (Symantec); Trojan-Dropper.Win32.NSIS.vz (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Dropped:Trojan.Generic.4982818 (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. It may be manually installed by a user.
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.
It may be manually installed by a user.
Installation
This Trojan drops the following files:
- %System Root%\ipconfig.txt
- %Application Data%\MyIEDat\main.ini
- %Application Data%\NetHome\main.ini
- %Desktop%\uuse-5905.exe
- %User Temp%\nsb42.tmp\InstallOptions.dll
- %User Temp%\nsb42.tmp\ioSpecial.ini
- %User Temp%\nsb42.tmp\modern-wizard.bmp
- %User Temp%\nsz3F.tmp\Math.dll
- %User Temp%\~nsu.tmp\Au_.exe
- %Program Files%\baidu\dsop7.xml
- %Program Files%\baidu\msfsg.exe
- %Program Files%\baidu\tempnethome18.ini
- %Program Files%\baidu\uninst18.exe
- %System%\nethome32.dll
- %System%\netplayone\MyIEData
- %System%\netplayone\MyIEData\main.ini
- %System%\netplayone\MyIEDataSysDat.bin
- %System%\netplayone\netplayone.dll
- %System%\drivers\siglow.dll
- %System%\drivers\siglow.sys
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %Desktop% is the desktop folder, where it usually is C:\Documents and Settings\{user name}\Desktop in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\Desktop in Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
It creates the following folders:
- %Program Files%\baidu
- %User Temp%\nsz3F.tmp
- %User Temp%\nsb42.tmp
- %Application Data%\MyIEData
- %Application Data%\NetHome
- %System%\netplayone
- %User Temp%\~nsu.tmp
(Note: %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
Autostart Technique
This Trojan registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\siglow
DisplayName = "siglow Miniport"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\siglow
ImagePath = "%System%\drivers\siglow.sys"
Other System Modifications
This Trojan adds the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\NetHomeIDE
Description = "NetHomeIDE Audit Service."
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\NetHomeIDE
ImagePath = "%System%\svchost.exe -k mysysgroup3"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\SvcHost
mysysgroup3 = "NetHomeIDE"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\WinSock2\speednet_sph
PathName = "%System%\netplayone\netplayone.dll"
It also creates the following registry entry(ies) as part of its installation routine:
HKEY_LOCAL_MACHINE\SOFTWARE\gameplayer
(Default) = "08741501213154947354507"
Other Details
This Trojan connects to the following possibly malicious URL:
- {BLOCKED}j.{BLOCKED}e.cn
- {BLOCKED}q.com
- {BLOCKED}.{BLOCKED}e.cn
SOLUTION
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
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 3
Restart in Safe Mode
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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SvcHost
- mysysgroup3 = "NetHomeIDE"
- mysysgroup3 = "NetHomeIDE"
Step 5
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. 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\SYSTEM\CurrentControlSet\Services\WinSock2
- speednet_sph
- speednet_sph
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
- siglow
- siglow
- In HKEY_LOCAL_MACHINE\SOFTWARE
- gameplayer
- gameplayer
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
- NetHomeIDE
- NetHomeIDE
Step 6
Search and delete these folders
- %Program Files%\baidu
- %User Temp%\nsz3F.tmp
- %User Temp%\nsb42.tmp
- %Application Data%\MyIEData
- %Application Data%\NetHome
- %System%\netplayone
- %User Temp%\~nsu.tmp
Step 7
Search and delete these files
- %System Root%\ipconfig.txt
- %Desktop%\uuse-5905.exe
- %System%\nethome32.dll
- %System%\drivers\siglow.dll
- %System%\drivers\siglow.sys
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_BOHU.A. 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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