TROJ_JORIK.ELK
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 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 drops the following copies of itself into the affected system:
- %Program Files%\Ruwuat ifaui\Ejhwqxg.exe
(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).)
It creates the following folders:
- %Program Files%\Ruwuat ifaui
(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 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\Ruuica xriaywot
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Oljgcm eaciqa
Other System Modifications
This Trojan adds the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\MediaResources\msvideo
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Ruuica xriaywot
ReleiceName = "Oljgcm eaciqa"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Oljgcm eaciqa
ConnectGroup = "º«¹ú"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Oljgcm eaciqa
MarkTime = "2013-06-10 17:43"
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Oljgcm eaciqa
Description = "Aksngs xnkmgnok cqnnimuaqki"
Dropping Routine
This Trojan drops the following files:
- %System Root%\1500.vbs
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
Other Details
This Trojan deletes itself after execution.
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
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\SYSTEM\CurrentControlSet\Services
- Ruuica xriaywot
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
- Oljgcm eaciqa
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\MediaResources
- msvideo
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\SYSTEM\ControlSet001\Services\Ruuica xriaywot
- ReleiceName = "Oljgcm eaciqa"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Oljgcm eaciqa
- ConnectGroup = "º«¹ú"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Oljgcm eaciqa
- MarkTime = "2013-06-10 17:43"
- In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Oljgcm eaciqa
- Description = "Aksngs xnkmgnok cqnnimuaqki"
Step 5
Search and delete this file
- %System Root%\1500.vbs
Step 6
Search and delete this folder
- %Program Files%\Ruwuat ifaui
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_JORIK.ELK. 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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