TROJ_INJECTO.BTB
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.
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:
- {malware path and file name}.dll
- %Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
It creates the following folders:
- %Application Data%\FA8WOd9eoao
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
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
Tf3wFfBHf.exe = "%Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Tf3wFfBHf.exe = "%Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe"
It modifies the following registry entries to ensure it automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Shell = "cmd.exe"
(Note: The default value data of the said registry entry is Explorer.exe.)
Other System Modifications
This Trojan adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Command Processor
Autorun = "%Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Winlogon
Shell = "cmd.exe"
It modifies the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
EventMessageFile = "%System%\esent.dll"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
CategoryMessageFile = "%System%\esent.dll"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
CategoryCount = "1"
(Note: The default value data of the said registry entry is 10.)
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Eventlog\Application\
ESENT
TypesSupported = "7"
(Note: The default value data of the said registry entry is 7.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Command Processor
Autorun = "%Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
Name = "svchost.exe"
(Note: The default value data of the said registry entry is iexplore.exe.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
ID = "4117ed6"
(Note: The default value data of the said registry entry is 41107b81.)
Dropping Routine
This Trojan drops the following files:
- %User Temp%\GSYNGoiOT
- %System Root%\WBuFi
- %System Root%\oton\kybiIqOapb\athij\zmqjuxOkJ
- %System Root%\sFEjvc\dxsODdf.lft
- %System Root%\clrpp\tbyrn\zadoqSvEuK\exjcjCvV\NFLaOry.fbb
- %System Root%\Vnzmnf\WkwdAsnreY\xwhxaUtc
- %System Root%\uKigqgpqbw
- %System Root%\RCGfmjmbkW\Djngqn\itzkZ.fyf
- %System Root%\phoehzc\tvlguwA\bWpjuD.buj
- %System Root%\envawoA\dmxxoG\Zkvnkt\xFuBcz\xhUJVklIOnw.tgf
- %System Root%\worxa.wqy
- %System Root%\nBJshu\nQszrlGmwjj\vwgbTx\iolsLnGf
- %System Root%\qoxphumoqv\ckidqq.jkf
- %User Profile%\Application Data\AnWHUVClUg
- %User Profile%\Application Data\WJXqCFPHiJC
- %Application Data%\bc8g4yM35
- %User Profile%\Templates\pAIYF7pYO
(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 Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %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.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
Other Details
This Trojan connects to the following possibly malicious URL:
- http://{BLOCKED}pjyp.at/?{random characters}
This report is generated via an automated analysis system.
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
Identify and delete files detected as TROJ_INJECTO.BTB using either the Startup Disk or Recovery Console
Step 3
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
- Tf3wFfBHf.exe = "%Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- Tf3wFfBHf.exe = "%Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Command Processor
- Autorun = "%Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
- Shell = "cmd.exe"
Step 4
Restore these modified registry values
Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
- From: EventMessageFile = "%System%\esent.dll"
To: EventMessageFile = ""{random values}""
- From: EventMessageFile = "%System%\esent.dll"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
- From: CategoryMessageFile = "%System%\esent.dll"
To: CategoryMessageFile = ""{random values}""
- From: CategoryMessageFile = "%System%\esent.dll"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
- From: CategoryCount = "1"
To: CategoryCount = ""10""
- From: CategoryCount = "1"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\ESENT
- From: TypesSupported = "7"
To: TypesSupported = ""7""
- From: TypesSupported = "7"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Command Processor
- Autorun = "%Application Data%\FA8WOd9eoao\Tf3wFfBHf.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication
- From: Name = "svchost.exe"
To: Name = ""iexplore.exe""
- From: Name = "svchost.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication
- From: ID = "4117ed6"
To: ID = ""41107b81""
- From: ID = "4117ed6"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
- From: Shell = "cmd.exe"
To: Shell = ""Explorer.exe""
- From: Shell = "cmd.exe"
Step 5
Search and delete these components
- %User Temp%\GSYNGoiOT
- %System Root%\WBuFi
- %System Root%\oton\kybiIqOapb\athij\zmqjuxOkJ
- %System Root%\sFEjvc\dxsODdf.lft
- %System Root%\clrpp\tbyrn\zadoqSvEuK\exjcjCvV\NFLaOry.fbb
- %System Root%\Vnzmnf\WkwdAsnreY\xwhxaUtc
- %System Root%\uKigqgpqbw
- %System Root%\RCGfmjmbkW\Djngqn\itzkZ.fyf
- %System Root%\phoehzc\tvlguwA\bWpjuD.buj
- %System Root%\envawoA\dmxxoG\Zkvnkt\xFuBcz\xhUJVklIOnw.tgf
- %System Root%\worxa.wqy
- %System Root%\nBJshu\nQszrlGmwjj\vwgbTx\iolsLnGf
- %System Root%\qoxphumoqv\ckidqq.jkf
- %User Profile%\Application Data\AnWHUVClUg
- %User Profile%\Application Data\WJXqCFPHiJC
- %Application Data%\bc8g4yM35
- %User Profile%\Templates\pAIYF7pYO
Step 6
Search and delete this folder
- %Application Data%\FA8WOd9eoao
Step 7
Scan your computer with your Trend Micro product to delete files detected as TROJ_INJECTO.BTB. 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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