W32/Agobot-ND

Please follow the instructions for removing worms.

Replace the Hosts file from a backup or edit it in Notepad to remove the changes that the worm has made.

You will also need to edit the following registry entries, if they are present. 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 entries:

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\
sounofts = sounofts.exe

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices\
sounofts = sounofts.exe

and delete them if they exist.

Close the registry editor.

Sophos anti-virus products since version 3.85 have been capable of detecting this worm as W32/Agobot-Gen without requiring an update.

W32/Agobot-ND is a backdoor Trojan and worm which spreads to computers protected by weak passwords. It may also attempt to spread via the Microsoft LSASS vulnerability.

For further information on this vulnerability see Microsoft security bulletin MS04-011.

When first run, W32/Agobot-ND moves itself to the Windows system folder as sounofts.exe and creates the following registry entries to run itself on logon:

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\
sounofts = sounofts.exe

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices\
sounofts = sounofts.exe

W32/Agobot-ND also drops a helper file to the Windows system folder named wormride.dll which is already detected by Sophos as W32/Agobot-IL.

The worm runs continuously in the background providing backdoor access to the computer.

The worm attempts to terminate and disable various anti-virus and security-related programs and modifies the HOSTS file located at %WINDOWS%\System32\Drivers\etc\HOSTS, mapping selected anti-virus websites to the loopback address 127.0.0.1 in an attempt to prevent access to these sites. Typically the following mappings will be appended to the HOSTS file:

127.0.0.1 www.symantec.com
127.0.0.1 securityresponse.symantec.com
127.0.0.1 symantec.com
127.0.0.1 www.sophos.com
127.0.0.1 sophos.com
127.0.0.1 www.mcafee.com
127.0.0.1 mcafee.com
127.0.0.1 liveupdate.symantecliveupdate.com
127.0.0.1 www.viruslist.com
127.0.0.1 viruslist.com
127.0.0.1 viruslist.com
127.0.0.1 f-secure.com
127.0.0.1 www.f-secure.com
127.0.0.1 kaspersky.com
127.0.0.1 kaspersky-labs.com
127.0.0.1 www.avp.com
127.0.0.1 www.kaspersky.com
127.0.0.1 avp.com
127.0.0.1 www.networkassociates.com
127.0.0.1 networkassociates.com
127.0.0.1 www.ca.com
127.0.0.1 ca.com
127.0.0.1 mast.mcafee.com
127.0.0.1 my-etrust.com
127.0.0.1 www.my-etrust.com
127.0.0.1 download.mcafee.com
127.0.0.1 dispatch.mcafee.com
127.0.0.1 secure.nai.com
127.0.0.1 nai.com
127.0.0.1 www.nai.com
127.0.0.1 update.symantec.com
127.0.0.1 updates.symantec.com
127.0.0.1 us.mcafee.com
127.0.0.1 liveupdate.symantec.com
127.0.0.1 customer.symantec.com
127.0.0.1 rads.mcafee.com
127.0.0.1 trendmicro.com
127.0.0.1 www.trendmicro.com
127.0.0.1 www.grisoft.com