VBS_AGENT.AVKG
Windows 2000, XP, Server 2003
Threat Type: Worm
Destructiveness: No
Encrypted: No
In the wild: Yes
TECHNICAL DETAILS
11,330 bytes
Script
No
06 May 2010
Installation
This worm drops the following copies of itself into the affected system:
- %User Profile%\My Documents\df5srvc.bfe
- %System Root%\{all folders found}\desktop.ini
- %System Root%\desktop.ini
(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Df5serv = Wscript.exe //e:VBScript "%User Profile%\My Documents\df5srvc.bfe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Explorer = Wscript.exe //e:VBScript "%Application Data%\Microsoft\CD Burning\dekstop.ini"
Other System Modifications
This worm adds the following registry keys:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\SuperHidden
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
It adds the following registry entries as part of its installation routine:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\SuperHidden
WarningIfNotDefault = fandy love yuyun
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableRegistrytools = 1
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableTaskMgr = 1
It modifies the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Start Page = http://www.{BLOCKED}t.co.nr
(Note: The default value data of the said registry entry is {default homepage}.)
It modifies the following registry entries to hide files with Hidden attributes:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\SuperHidden
UncheckedValue = 1
(Note: The default value data of the said registry entry is 0.)
Propagation
The said .INF file contains the following strings:
[autorun]
open=WScript.exe //e:VBScript dekstop.ini auto
shell\open=Open
shell\open\Command=WScript.exe //e:VBScript dekstop.ini auto
shell\open\Default=1
shell\explore=Explore
shell\explore\Command=WScript.exe //e:VBScript dekstop.ini auto
Dropping Routine
This worm drops the following files:
- %System Root%\autorun.inf - detected by Trend Micro as Mal_Otorun1
- %System Root%\{all folders found}\autorun.inf - detected by Trend Micro as Mal_Otorun1
- %System Root%\Microsoft.lnk
- %System Root%\Aplikasi.lnk
- %System Root%\{all folders found}\Microsoft.lnk
- %System Root%\{all folders found}\Aplikasi.lnk
- %System%\Serv60d.dll - nonmalicious
- %System%\auto.exe - detected by Trend Micro as Mal_Otorun1
- %System%\v.doc - nonmalicious
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.. %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.)
Other Details
This worm does the following:
- It creates shortcut links of all folders found in the %System Root% folder.
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
SOLUTION
8.900
7.150.07
06 May 2010
5/6/2010 12:00:00 AM
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
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
- Df5serv = Wscript.exe //e:VBScript %User Profile%\My Documents\df5srvc.bfe
- Df5serv = Wscript.exe //e:VBScript %User Profile%\My Documents\df5srvc.bfe
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- Explorer = Wscript.exe //e:VBScript %Application Data%\Microsoft\CD Burning\dekstop.ini
- Explorer = Wscript.exe //e:VBScript %Application Data%\Microsoft\CD Burning\dekstop.ini
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\Microsoft\Windows\CurrentVersion\Explorer\Advanced\
- Folder
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\
- System
Step 4
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_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
- From: Start Page = http://www.{BLOCKED}t.co.nr To: Start Page = about:blank
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\SuperHidden
- From: UncheckedValue = 0< To: UncheckedValue = 1
Step 5
Search and delete this file
- %System Root%\{all folders found}\Aplikasi.lnk
- %System Root%\{all folders found}\autorun.inf - detected by Trend Micro as Mal_Otorun1
- %System Root%\{all folders found}\Microsoft.lnk
- %System Root%\Aplikasi.lnk
- %System Root%\autorun.inf - detected by Trend Micro as Mal_Otorun1
- %System Root%\Microsoft.lnk
- %System%\auto.exe - detected by Trend Micro as Mal_Otorun1
- %System%\Serv60d.dll - nonmalicious
- %System%\v.doc - nonmalicious
Step 6
Search and delete AUTORUN.INF files created by VBS_AGENT.AVKG that contain these strings
Step 7
Scan your computer with your Trend Micro product to delete files detected as VBS_AGENT.AVKG. 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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