WORM_AUTORUN.FKO
Backdoor:Win32/FlyAgent.F (Microsoft), Win32/AutoRun.FlyStudio.WQ (Kaspersky), Worm.Win32.FlyStudio (Ikarus)
Windows 2000, Windows XP, Windows Server 2003

Threat Type: Worm
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
This worm drops copies of itself in removable drives. These dropped copies use the names of the folders located on the said drives for their file names. 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
Installation
This worm drops the following copies of itself into the affected system:
- %System%\{random 4}\{random file name}.EXE
(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 drops the following file(s)/component(s):
- %System%\{random 3}\cnvpe.fne
- %System%\{random 3}\dp1.fne
- %System%\{random 3}\eAPI.fne
- %System%\{random 3}\HtmlView.fne
- %System%\{random 3}\internet.fne
- %System%\{random 3}\krnln.fnr
- %System%\{random 3}\RegEx.fnr
- %System%\{random 3}\shell.fne
- %System%\{random 3}\spec.fne
(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 creates the following folders:
- %System%\{random 1}
- %System%\{random 2}
- %System%\{random 3}
- %System%\{random 4}
(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.)
Autostart Technique
This worm drops the following file(s) in the Windows User Startup folder to enable its automatic execution at every system startup:
- %User Startup%\{random file name}.lnk
(Note: %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.)
Propagation
This worm drops the following copy(ies) of itself in all removable drives:
- Recycle.exe
It drops copies of itself in removable drives. These dropped copies use the names of the folders located on the said drives for their file names.
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:
[AutoRun]
open=Recycle.exe
shell\1=´ò¿ª(&O)
shell\1\Command=Recycle.exe
shell\2\=ä¯ÀÀ(&B)
shell\2\Command=Recycle.exe
shellexecute=Recycle.exe
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
Identify and terminate files detected as WORM_AUTORUN.FKO
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
Step 3
Search and delete AUTORUN.INF files created by WORM_AUTORUN.FKO that contain these strings
open=Recycle.exe
shell\1=´ò¿ª(&O)
shell\1\Command=Recycle.exe
shell\2\=ä¯ÀÀ(&B)
shell\2\Command=Recycle.exe
shellexecute=Recycle.exe
Step 4
Search and delete these folders
%System%\{random 2}
%System%\{random 3}
%System%\{random 4}
Step 5
Search and delete this file
Step 6
Scan your computer with your Trend Micro product to delete files detected as WORM_AUTORUN.FKO. 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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