WORM_ONLINEGA.SB
Windows 2000, Windows XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Worm
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It adds registry entries to enable its automatic execution at every system startup.
It modifies registry entries to hide files with System and Read-only attributes.
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
It deletes the initially executed copy of itself.
TECHNICAL DETAILS
108,038 bytes
EXE
Yes
07 Apr 2009
Arrival Details
This worm 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 worm drops the following files:
- %System%\mmvo0.dll
(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 copies of itself into the affected system:
- %System%\mmvo.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.)
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
mmva = "%System%\mmvo.exe"
Other System Modifications
This worm modifies the following registry entries to hide files with System and Read-only attributes:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
Hidden = "2"
(Note: The default value data of the said registry entry is 1.)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "0"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
SHOWALL
CheckedValue = "0"
(Note: The default value data of the said registry entry is 1.)
Propagation
This worm drops the following copy of itself in all physical and removable drives:
- {Drive Letter}:\w.exe
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:
;{Random Characters}
[AutoRun]
;{Random Characters}
open=w.exe
;{Random Characters}
shell\open\Command=w.exe
;{Random Characters}
shell\open\Default=1
;{Random Characters}
shell\explore\Command=w.exe
;{Random Characters}
Download Routine
This worm downloads an updated copy of itself from the following website(s):
- http://{BLOCKED}5.com/rbv/uu.rar
Other Details
This worm deletes the initially executed copy of itself