TROJ_DLOAD.RKY
Trojan:Win32/Meredrop (Microsoft), Backdoor.Graybird (Symantec), PWS-OnlineGames.fw (McAfee)
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 adds certain registry entries to disable the Task Manager. This action prevents users from terminating the malware process, which can usually be done via the Task Manager.
It modifies certain registry entries to hide Hidden files. It deletes itself after execution.
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 adds the following possibly malicious files or file components:
- %System Root%\Por.aed
- %System Root%\sys13
- %System Root%\sysLoad
- %Program Files%\MSDN\000000001
- %Program Files%\MSDN\hehex.sys
- %Windows%\TXplatform.exe
- %System%\ihdggei.exe
- %System%\inertno.exe
- %System%\ttjj36.ini
- %System%\TXplatx
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).. %Windows% is the Windows folder, which is usually C:\Windows.. %System% is the Windows system folder, which is usually C:\Windows\System32.)
It creates the following folders:
- %Program Files%\MSDN
(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).)
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
SoundMan = "TXplatform.exe"
It modifies the following registry entries to ensure it automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\helpsvc
ImagePath = "%SystemRoot%\System32\svchost.exe -k netsvcs,"C:\WINDOWS\system32\inertno.exe""
(Note: The default value data of the said registry entry is "%SystemRoot%\System32\svchost.exe -k netsvcs".)
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\lhlh1314
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Enum\Root\LEGACY_LHLH1314
Other System Modifications
This Trojan adds the following registry entries to disable the Task Manager:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
taskmgr.exe
Debugger = "svchost.exe"
Download Routine
This Trojan accesses the following websites to download files:
- http://{BLOCKED}.{BLOCKED}.245.172/rc/xms/gx2.txt
- http://{BLOCKED}.{BLOCKED}.45.106/rc/xms/gx2.txt
- http://{BLOCKED}.{BLOCKED}.45.106/rc/zj/notepde.jpg
- http://{BLOCKED}.{BLOCKED}.45.106/rc/zj/ww.txt
- http://{BLOCKED}.{BLOCKED}.45.106/rc/zj/wwan.jpg
- http://{BLOCKED}.{BLOCKED}.233.43/ip/ip.asp
- http://{BLOCKED}.{BLOCKED}.233.43/rc/need.jpg
- http://{BLOCKED}d.20s1.com/qb/08122.txt
- http://{BLOCKED}k.in/rc/xms/gx2.txt
- http://{BLOCKED}k.in/rc/zj/notepde.jpg
- http://{BLOCKED}k.in/rc/zj/ww.txt
- http://{BLOCKED}k.in/rc/zj/wwan.jpg
Other Details
This Trojan modifies the following registry entries to hide Hidden files:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
SHOWALL
CheckedValue = "6"
(Note: The default value data of the said registry entry is "1".)
It deletes itself after execution.
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
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. 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
- lhlh1314
- lhlh1314
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\Root
- LEGACY_LHLH1314
- LEGACY_LHLH1314
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\CurrentVersion\Run
- SoundMan = "TXplatform.exe"
- SoundMan = "TXplatform.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\taskmgr.exe
- Debugger = "svchost.exe"
- Debugger = "svchost.exe"
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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\SHOWALL
- From: CheckedValue = "6"
To: CheckedValue = "1"
- From: CheckedValue = "6"
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\helpsvc
- From: ImagePath = "%SystemRoot%\System32\svchost.exe -k netsvcs,"C:\WINDOWS\system32\inertno.exe""
To: ImagePath = "%SystemRoot%\System32\svchost.exe -k netsvcs"
- From: ImagePath = "%SystemRoot%\System32\svchost.exe -k netsvcs,"C:\WINDOWS\system32\inertno.exe""
Step 6
Search and delete this folder
- %Program Files%\MSDN
Step 7
Search and delete these files
- %System Root%\Por.aed
- %System Root%\sys13
- %System Root%\sysLoad
- %Program Files%\MSDN\000000001
- %Program Files%\MSDN\hehex.sys
- %Windows%\TXplatform.exe
- %System%\ihdggei.exe
- %System%\inertno.exe
- %System%\ttjj36.ini
- %System%\TXplatx
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_DLOAD.RKY. 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.
Did this description help? Tell us how we did.