The worm appends itself to the end of legitimate outgoing messages as a signature. When receiving the message, the worm

will automatically insert a copy of itself into the appropriate StartUp directory of the Windows operating system for both

English and French language versions. The file created is named KAK.HTA.

The worm utilizes a known Microsoft Outlook Express security hole, Scriptlet.Typelib, so that a viral file is created on the

system without having to run any attachment. Simply reading the received email message will cause the virus to be placed on the system.

Microsoft has patched this security hole. The patch is available from Microsoft's website. If you have a patched version of Outlook Express,

this worm will not work automatically.

HTA files are executed by current versions of Microsoft Internet Explorer or Netscape Navigator. The system must be rebooted for this file to

be executed. Once executed, the worm modifies the registry key:


HKCU/Identities/<Identity>/Software/
Microsoft/Outlook/Express/5.0/signatures

in order to add its own signature file, which is the infected KAK.HTA file. This causes all outgoing mail to be appended by the worm. In addition,

the registry key:


HKLM/Software/Microsoft/Windows/
CurrentVersion/Run/cAgOu

is added which causes the worm to be executed each time the computer is restarted.

Finally, if it is the first of the month and the hour is 17 (5:00pm), the following message is displayed:


Kagou-Anti-Kro$oft says not today!

and Windows is sent the message to shutdown.

Removal:

Delete the following file: KAK.HTA
Delete the following registry key:
HKLM/Software/Microsoft/Windows/
CurrentVersion/Run/cAgOu