Technical Information
To ensure autorun and distribution:
Modifies the following registry keys:
- [<HKCU>\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run] 'winlogon' = '%WINDIR%\System\winlogon.exe'
- [<HKLM>\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon] 'Userinit' = '<SYSTEM32>\userinit.exe,%WINDIR%\System\winlogon.exe'
- [<HKLM>\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Run] 'winlogon' = '%WINDIR%\System\winlogon.exe'
- [<HKCU>\Software\Microsoft\Windows\CurrentVersion\Run] 'winlogon' = '%WINDIR%\System\winlogon.exe'
- [<HKLM>\SOFTWARE\Microsoft\Windows\CurrentVersion\Run] 'winlogon' = '%WINDIR%\System\winlogon.exe'
Creates the following files on removable media:
- <Drive name for removable media>:\Autorun.inf
- <Drive name for removable media>:\SYSTEM.EXE
Malicious functions:
To bypass firewall, removes or modifies the following registry keys:
- [<HKLM>\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List] '%WINDIR%\system\winlogon.exe' = '%WINDIR%\system\winlogon.exe:*:Enabled:winlogon'
Creates and executes the following:
- '%WINDIR%\system\winlogon.exe' Kill(<Full path to virus>)
Executes the following:
- '<SYSTEM32>\netsh.exe' firewall add allowedprogram "%WINDIR%\System\winlogon.exe" winlogon Enable
Modifies file system :
Creates the following files:
- %WINDIR%\system\RCX1.tmp
- %WINDIR%\system\winlogon.exe
Sets the 'hidden' attribute to the following files:
- <Drive name for removable media>:\Autorun.inf
- <Drive name for removable media>:\SYSTEM.EXE
- %WINDIR%\system\winlogon.exe
Deletes the following files:
- %WINDIR%\system\winlogon.exe
Moves the following files:
- from %WINDIR%\system\RCX1.tmp to %WINDIR%\system\winlogon.exe
Deletes itself.
Network activity:
Connects to:
- 'bl#####th.dyndns.info':3178
UDP:
- DNS ASK bl#####th.dyndns.info
Miscellaneous:
Searches for the following windows:
- ClassName: 'Indicator' WindowName: ''
- ClassName: '' WindowName: 'BHH'