Zafi.C is a variant of the Zafi mass-mailing worm family.
This worm sends email messages with infected attachments in several
different languages.
The payload of Zafi.C is a Distributed Denial-of-Service attack against
google.com, microsoft.com and www.miniszterelnok.hu.
System Infection
When the worm's file is run, it copies itself as 'svchost.com'
to Windows System folder and creates a startup key for this file
in the Registry:
[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"_svchost.con" = "%SystemDir%\svchost.com"
%SystemDir% represents the Windows System folder name, for
example C:\Windows\System32 on Windows XP systems.
Another copy is created in the same directory as 'svchost.con'.
Zafi.C keeps its state information in the registry under
[HKEY_LOCAL_MACHINE\Software\Microsoft\UpdateZ3]
Email propagation
Zafi.C collects email addresses from Windows Address Book and
different files (eg. HTM, TXT, MBX, etc).
The worm composes the messages it sends based on complex rules
in many different languages. The email attachments might have
double extensions (composed from .DOC/.TXT and .EXE/.SCR).
Payload
The payload of Zafi.C is a Distributed Denial-of-Service attack
against
google.com
microsoft.com
www.miniszterelnok.hu
Detection for this malware was published on October 27th, 2004
in the following F-Secure Anti-Virus updates:
[FSAV_Database_Version]
Version=2004-10-27_03
Write-up:
F-Secure Antivirus Research Team, October 27th, 2004;
F-Secure Corporation