WORM_AUTOIT.AQ
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Worm
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This worm deletes itself after execution.
TECHNICAL DETAILS
Installation
This worm drops the following file(s)/component(s):
- %system%\autorun.inf
- %User Temp%\suicide.bat
(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.)
It drops the following copies of itself into the affected system:
- %system%\csrcs.exe
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
csrcs = %system%\csrcs.exe
It modifies the following registry entries to ensure it automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Shell = Explorer.exe csrcs.exe
(Note: The default value data of the said registry entry is Explorer.exe.)
Other System Modifications
This worm adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Run
Propagation
The said .INF file contains the following strings:
;{garabage}
[AuTOrUn
;{garabage}
open=mcpwoz.exe
;{garabage}
shell\open\Command=mcpwoz.exe
;{garabage}
shell\open\Default=1
;{garabage}
Other Details
This worm does the following:
- The file %User Temp%\suicide.bat contains the following strings:
loop:
del "%malware path%\%malware name%"
ping -n 5 -w 250 127.0.0.1
if exist "%malware path%\%malware name%" goto loop
del suicide.bat - It drops the following empty file in all physical and removable drives:
- xerfoj6
It deletes itself after execution.
SOLUTION
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 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\Microsoft\Windows\CurrentVersion\policies\Explorer\
Run
Step 3
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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\WinlogonShell = Explorer.exe csrcs.exeShell = Explorer.exe
Step 4
Search and delete this file
Step 5
Search and delete AUTORUN.INF files created by WORM_AUTOIT.AQ that contain these strings
;{garabage}
[AuTOrUn
;{garabage}
open=mcpwoz.exe
{garabage}
shell\open\Command=mcpwoz.exe
;{garabage}
shell\open\Default=1
;{garabage}
Step 6
Scan your computer with your Trend Micro product to delete files detected as WORM_AUTOIT.AQ. 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.
Did this description help? Tell us how we did.