Effects 

Zafi.D has the following effects:

• It has backdoor characteristics, as it opens the port 8181 and waits for a file to be transferred through it. Zafi.D executes this file, which is usually other malware.
• It impedes access to applications that contain the text strings reged, msconfig or task.
• It displays a fake error message on screen the first time it is run:
  
  

Infection strategy 

Zafi.D creates the following files:

• NORTON UPDATE.EXE in the Windows system directory. This file is a copy of the worm.
• Several files with a random name and a DLL extension in the Windows system directory. These files are copies of the worm.
• S.CM in the root directory of the C: drive. This file contains a list of programmed tasks.
• Several files with a DLL extension, which contain the e-mail addressed that Zafi.D gathers on the affected computer.
• Several copies of itself in all the directories whose names contain the text string share, upload or music.

Zafi.D creates the following entries in the Windows Registry:

• HKEY_LOCAL_MACHINE\ SOFTWARE\ Microsoft\ Windows\ CurrentVersion\ Run
  Wxp4 = %sysdir%\ Norton Update.exe
  where %sysdir% is the Windows system directory.
  By creating this entry, Zafi.D ensures that it is run whenever Windows is started.
• HKEY_LOCAL_MACHINE \ SOFTWARE\ Microsoft\ Wxp4
  Zafi.D uses this entry in order to store several parameters.

Means of transmission 

Zafi.D spreads via e-mail and through peer-to-peer (P2P) file sharing programs.

1.- Transmission via e-mail.

Zafi.D follows the routine below:

• It reaches the computer in an e-mail message with variable characteristics.
  That message can be written in different languages, depending on the recipient's domain. For those domains that are not included in the list below, the message will be written in English.
  These e-mail messages pass themselves off as Christmas greetings.
  
  Note: any of the following subjects could be preceded by the text strings Re:, Fw:, or they could even be empty.
  
  Hungary (.hu):
  Sender:
  T. Maria
  Subject:
  boldog karacsony...
  Message:
  Kellemes Ünnepeket!
  
  Spain (.es) and Mexico (.mx):
  Sender:
  N. Fernandez
  Subject:
  Feliz Navidad!
  Message:
  Feliz Navidad!
  Attachments:
  The name of the attached file contains the text string NAVIDAD.
  
  Denmark (.dk):
  Sender:
  V. Jensen
  Subject:
  Christmas Kort!
  Message:
  Glaedelig Jul!
  Attachments:
  The name of the attached file contains the text string EKORT.
  For example:
  
  
  
  Sweden (.se):
  Sender:
  J. Anderson
  Subject:
  Christmas Vykort!
  Message:
  God Jul!
  Attachments:
  The name of the attached file contains the text string VYKORT.
  
  Norway (.no):
  Sender:
  M. Emma
  Subject:
  Christmas Postkort!
  Message:
  God Jul!
  Attachments:
  The name of the attached file contains the text string POSTKORT.
  
  Finland (.fi):
  Sender:
  M. Virtanen
  Subject:
  Christmas postikorti!
  Message:
  Iloista Joulua!
  Attachments:
  The name of the attached file contains the text string POSTIKORTI.
  
  Lithuania (.lt):
  Sender:
  C. Lina
  Subject:
  Christmas Atviruka!
  Message:
  Naujielji Metai!
  Attachments:
  The name of the attached file contains the text string ATVIRUKA.
  
  Poland (.pl):
  Sender:
  S. Ewa
  Subject:
  Christmas - Kartki!
  Message:
  Wesolych Swiat!
  Attachments:
  The name of the attached file contains the text string KARTKI.
  
  Germany (.de) and Austria (.at):
  Sender:
  H. Irene
  Subject:
  Weihnachten card
  Message:
  Fröhliche Weihnachten!
  Attachments:
  The name of the attached file contains the text string WEIHNACHTEN.
  
  Netherlands (.nl):
  Sender:
  R. Cornel
  Subject:
  Prettige Kerstdagen!
  Message:
  Prettige Kerstdagen!
  Attachments:
  The name of the attached file contains the text string KERTSDAGEN.
  
  Czech Republic (.cz):
  Sender:
  V. Dusan
  Subject:
  Christmas pohlednice
  Message:
  Veselé Vánoce!
  Attachments:
  The name of the attached file contains the text string POHLEDNICE.
  
  France (.fr):
  Sender:
  J. Martin
  Subject:
  Joyeux Noel!
  Message:
  Joyeux Noel!
  Attachments:
  The name of the attached file contains the text string ECARTE.
  
  Italy (.it):
  Sender:
  T. Antonio
  Subject:
  Buon Natale!
  Message:
  Buon Natale!
  Attachments:
  The name of the attached file contains the text string CARTOLINE.
  
  Romania (.ru):
  Sender:
  V. Tatyana
  Attachments:
  The name of the attached file contains the text string CARD.
  
  For any domains not included in the previous list, the e-mail message has the following characteristics:
  Sender:
  Pamela M
  Subject:
  Merry Christmas!
  Message:
  Happy Holiday!
  Attachments:
  The name of the attached file contains the text string POSTCARD.
  For example:
  
  
  The attached file will always have any of the following extensions: BAT, CMD, COM, PIF or ZIP.
  
• The computer will be affected when the attached file is run.
• Zafi.D looks for e-mail addresses in files with the following extensions: ADB, ASP, DBX, EML, FPT, HTM, INB, MBX, PHP, PMR, SHT, TBB, TXT and WAB.
• Zafi.D sends a copy of itself out to all the addresses gathered, using its own SMTP engine. However, it does not send itself out to those addresses containing any of the following text strings:
  admi, cafee, google, help, hotm, info, kasper, micro, msn, panda, secur, sopho, suppor, syman, trend, use, viru, webm, win and yaho.

2.- Transmission through P2P file sharing programs.

Zafi.D carries out the routine below:

• It creates copies of itself in those directories whose full path contains any of the following text strings: share, upload and music.
  By doing so, Zafi.D attempts to make copies of itself in the shared directories of the file sharing programs.
• It makes copies of itself with the file names:
  ICQ 2005a new!.exe
  winamp 5.7 new!.exe
   
• Other users of these programs can remotely access these shared directories and download these files to their computers, thinking that they are useful computer programs, etc. However, these users will actually download a copy of Zafi.D.
• When the downloaded file is run, these computers will become affected by Zafi.D.

Further Details  

Zafi.D is 11,745 bytes in size, and it is compressed with FSG.