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Panda Protection

Virus Encyclopedia

Welcome to the Virus Encyclopedia of Panda Security.

Encyclopedia GetVirusCard True 0

Klez

 
Threat LevelModerate threatDamageHighDistributionNot widespread
Common name:Klez
Technical name:W32/Klez
Threat level:Low
Alias:Klez.A,, W32/Klez.A
Type:Worm
Subtype: Trojan
Effects:  It overwrites files and adds an EXE extension to them. It drops the Elkern.C virus in the computer.

Affected platforms:

Windows XP/2000/NT/ME/98/95

First detected on:
Detection updated on:Oct. 31, 2007
StatisticsNo
Proactive protection:
Yes, using TruPrevent Technologies
Family:KLEZ

Brief Description 

    

Klez is a worm that reaches computers in an e-mail message with a variable subject.

Klez carries out its infection when the e-mail attachment is run.

Klez poses the following threats:

  • It automatically and rapidly spreads to all the contacts in the Address Book. It can send several infected messages to the same user.
  • It deletes certain files.
  • It drops the Elkern.C virus in the affected computer, which prevents it from starting up correctly and renders certain programs unusable.

Visible Symptoms 

    

Klez is difficult to recognize because it reaches computers hidden in e-mail messages with variable characteristics. The most common subjects are:

How are you?

Can you help me?

We want peace

Where will you go?

Congratulations!!!

Don't cry

For more information consult the section Means of transmission.