TROJ_ALUREON.DSO
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Trojan
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This Trojan arrives as a file that exports the functions of other malware/grayware. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It connects to certain URLs. It may do this to remotely inform a malicious user of its installation. It may also do this to download possibly malicious files onto the computer, which puts the computer at a greater risk of infection by other threats.
It opens a hidden Internet Explorer window.
TECHNICAL DETAILS
196,624 bytes
PE
29 Jan 2011
Patches files
Arrival Details
This Trojan arrives as a file that exports the functions of other malware/grayware.
It 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:
- %System%\{random file name}.dll
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
It injects itself into the following processes running in the affected system's memory:
- explorer.exe
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\{random service name}
ImagePath = "%System Root%\System32\svchost.exe -k netsvcs"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\{random service name}\Parameters
ServiceDll = "{malware path and file name}"
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\{random service name}
DisplayName = "{random service name} System Services"
It adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
{malware file name} = "Rundll32.exe {malware path and file name},Rundll32Main"
Other System Modifications
This Trojan adds the following registry keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\MediaResources\msvideo
Download Routine
This Trojan connects to the following malicious URLs:
- http://www.{BLOCKED}ver.com/xcip.asp
Other Details
This Trojan opens a hidden Internet Explorer window.
It does the following:
- Selects a. DLL in the Windows system folder and copies it at %System%\{file name}.dll.obak. It then overwrites %System%\{file name}.dll with a copy of itself.
- Copies the file %System%\conime.exe as %System%\eminoc_bd.dll, and the file %System%\spoolsv.exe as %System%\vsloops_bd.dll. It then patches the files %System%\conime.exe and %System%\spoolsv.exe with code that automatically loasd this Trojan when the patched files are executed. Trend Micro detects the patched files are detected as PTCH_ALUREON.DSO.
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
SOLUTION
8.900
7.800.03
29 Jan 2011
7.801.00
29 Jan 2011
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Remove malware files dropped/downloaded by TROJ_ALUREON.DSO
- PTCH_ALUREON.DSO
Step 3
Scan your computer with your Trend Micro product and note files detected as TROJ_ALUREON.DSO
Step 4
Restart in Safe Mode
Step 5
Search and delete the file detected as TROJ_ALUREON.DSO
Step 6
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
- {malware file name} = Rundll32.exe {malware path and file name},Rundll32Main
Step 7
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
- {random service name}
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\MediaResources
- msvideo
Step 8
Restoring a File to its Original Location
- Click Start>Run.
- In the text box, type the following:
command /c copy %System%\eminoc_bd.dll %System%\conime.exe
command /c copy %System%\vsloops_bd.dll %System%\spoolsv.exe
command /c copy %System%\{file name}.dll.obak %System%\{file name}.dll - Press Enter.
Step 9
Search and delete these files
- %System%\eminoc_bd.dll
- %System%\vsloops_bd.dll
- %System%\{file name}.dll.obak
Step 10
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_ALUREON.DSO. 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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