VBS_AUTORUN.BXI
Symantec: VBS.Runauto; Microsoft: Worm:VBS/Radier.B
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Worm
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
It drops a copy if itself along with the AUTORUN.INF file in mapped drives.
This worm arrives by connecting affected removable drives to a system. It arrives by accessing affected shared networks.
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
TECHNICAL DETAILS
15,414 bytes
VBS
Yes
23 Mar 2011
Arrival Details
This worm arrives by connecting affected removable drives to a system.
It arrives by accessing affected shared networks.
Installation
This worm drops the following copies of itself into the affected system:
- %System%\.vbe
- %Windows%\.vbe
(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.. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
explorer\run
{system name} = ".vbe"
Other System Modifications
This worm adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE
{system name} = ""
It modifies the following registry entries to hide files with Hidden attributes:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "0"
(Note: The default value data of the said registry entry is 1.)
Propagation
This worm drops the following copy(ies) of itself in all removable drives:
- .vbs
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
The said .INF file contains the following strings:
Raider 8.01
[autorun]
open=wscript.exe .\.vbs
shell\open\command=wscript.exe .\.vbs
shell\open\default=1
NOTES:
It also drops a copy if itself along with the AUTORUN.INF file in mapped drives.
SOLUTION
8.900
7.921.00
23 Mar 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
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\SOFTWARE
- {system name}
- {system name}
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\policies\explorer\run
- {system name} = ".vbe"
- {system name} = ".vbe"
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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
- From: ShowSuperHidden = "0"
To: "ShowSuperHidden" = "1"
- From: ShowSuperHidden = "0"
Step 6
Search and delete AUTORUN.INF files created by VBS_AUTORUN.BXI that contain these strings
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as VBS_AUTORUN.BXI. 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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