W32/Cellery-A

Please follow the instructions for removing worms.

Windows NT/2000/XP/2003

In Windows NT/2000/XP/2003 you will also need to edit the following registry entries. The removal of these entries is optional in Windows 95/98/Me. Please read the warning about editing the registry.

At the taskbar, click Start|Run. Type 'Regedit' and press Return. The registry editor opens.

Before you edit the registry, you should make a backup. On the 'Registry' menu, click 'Export Registry File'. In the 'Export range' panel, click 'All', then save your registry as Backup.

Locate the HKEY_LOCAL_MACHINE entry:

HKLM\Software\Microsoft\Windows\CurrentVersion\Run\
Systrsy
"format32.exe"

and delete it if it exists.

Each user has a registry area named HKEY_USERS\[code number indicating user]\. For each user locate the entry:

HKU\[code number]\Software\Microsoft\Windows\CurrentVersion\Run\
Systrsy
"format32.exe"

and delete it if it exists.

Close the registry editor.

W32/Cellery-A is a network worm for the Windows platform that spreads by copying itself to predefined network drives.

When first executed W32/Cellery-A drops itself to the Windows folder and plays a standard MIDI data file with the filename minuet.mid, opens an interactive Tetris-like game window and at the same time copies itself to the Windows system folder with the filename format32.exe.

The Cellery worm plays Tetris on your computer.

In order to be able to run automatically when Windows starts up the worm sets the registry entries:

HKLM\Software\Microsoft\Windows\CurrentVersion\Run\
Systrsy
"format32.exe"

HKCU\Software\Microsoft\Windows\CurrentVersion\Run\
Systrsy
"format32.exe"

format32.exe, when run, creates a copy of itself in Windows Tasks folder with the filename sys32.exe and establishes a corresponding background process.

W32/Cellery-A attempts to copy itself to the Tasks folder on the admin$ share and to the \Documents and Settings\All Users folder of the following network drives:

C$, D$, E$, G$ H$ and I$.