BKDR_MORIX.EO
[KV3.EXE]:Generic BackDoor.abf (McAfee); Trojan.Win32.Hosts2.gen (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse BackDoor.Generic_r.AFZ (AVG)
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Backdoor
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This backdoor 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 backdoor 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 backdoor creates the following folders:
- %System Root%/0617
- %Windows%\8A4CE9C0
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %Windows% is the Windows folder, which is usually C:\Windows.)
Autostart Technique
This backdoor adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
8A4CE9C0 = "%Windows%\8A4CE9C0\svchsot.exe"
Other System Modifications
This backdoor adds the following registry keys:
HKEY_CURRENT_USER\Software\WinRAR SFX
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\MediaResources\msvideo
HKEY_LOCAL_MACHINE\SYSTEM\InfoTime
It adds the following registry entries:
HKEY_CURRENT_USER\Software\WinRAR SFX
c%%0617 = "%System Root%/0617"
HKEY_LOCAL_MACHINE\SYSTEM\InfoTime
InfoTime = "20130711"
Dropping Routine
This backdoor drops the following files:
- __tmp_rar_sfx_access_check_146031
- hosts.txt
- 1.vbs
- 0617.bat
- kv3.exe
- %System%\drivers\etc\hosts.txt
(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)
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_CURRENT_USER\Software
- WinRAR SFX
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\MediaResources
- msvideo
- In HKEY_LOCAL_MACHINE\SYSTEM
- InfoTime
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
- 8A4CE9C0 = "%Windows%\8A4CE9C0\svchsot.exe"
- In HKEY_CURRENT_USER\Software\WinRAR SFX
- c%%0617 = "%System Root%/0617"
- In HKEY_LOCAL_MACHINE\SYSTEM\InfoTime
- InfoTime = "20130711"
Step 5
Search and delete these components
- __tmp_rar_sfx_access_check_146031
- hosts.txt
- 1.vbs
- 0617.bat
- kv3.exe
- %System%\drivers\etc\hosts.txt
Step 6
Search and delete these folders
- %System Root%/0617
- %Windows%\8A4CE9C0
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_MORIX.EO. 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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