* via http://theMezz.com/lists

New variant of the Klez worm 
By Robert Lemos 
Staff Writer, CNET News.com
April 17, 2002, 11:30 AM PT

A new variant of the Klez worm managed to squirm into computers in
some parts of Asia on Tuesday and appeared to be spreading in the
United States as of Wednesday.

Alternately known as Klez.g, Klez.h and Klez.k, depending on the
security advisory that's referring to it, the worm has its own e-mail
engine to mass mail itself to potential victims, and it also attempts
to deactivate some antivirus products. The worm can also spread to
shared drives connected to PCs via local area networks or LANs.

While the e-mail message in which the worm gift-wraps itself is
relatively standard, its ability to elude most antivirus products has
enabled it to spread fairly widely, said Alex Shipp, an antivirus
technologist for U.K.-based e-mail service provider MessageLabs.

"The author has changed enough of the bits to get past most virus
programs," Shipp said.

While MessageLabs rates the virus as a low threat, Shipp said the
rating is updated periodically, and he expects it to reach a high
rating when it does update. The company first detected the malicious
attachment late Monday and has seen the spread of the worm gradually

Different variants of the Klez worm have generally been among the Top
3 antivirus threats since the first version of the worm was released
in January. The Klez.e variant, which appeared last February, was
particularly voracious, quickly becoming one of the fastest-spreading
worms on the Internet.

Security-software maker Symantec upgraded the latest variant, which it
labeled W32.Klez.H, to a threat level of three from a previous rating
of two. The company categorizes threats on a scale of one, the lowest
threat, to five.

A worm of many subjects The worm arrives in an e-mail message with one
of 120 possible subject lines. There are 18 different standard subject
headings, including "let's be friends," "meeting notice," "some
questions," and "honey."  On top of those, seven other patterns exist,
such as "a x game" and "a x patch," where x can be one of 16 different
words, including "new,"  "WinXP," and the name of any of six major
antivirus companies.

In many circumstances, the worm doesn't need the victim to open it in
order to run. Instead, it takes advantage of a 12-month-old
vulnerability in Microsoft Outlook, known as the Automatic Execution
of Embedded MIME Type bug, to open itself automatically on unpatched
versions of Outlook.

The malicious program will find any network storage available on the
infected PC and copy itself to the remote disk drives using a random
file name and a .EXE, .PIF, .COM, .BAT, .SCR or .RAR extension.  
Occasionally, the file name will include a double extension.

The program will also cull e-mail addresses by searching a host of
different file types on the infected PC. Using its own mail program,
the worm will send itself off to those e-mail addresses. In addition,
it will use the addresses to create a fake "From:" field in the e-mail
message, disguising the actual source of the e-mail.

Finally, the worm attempts to disable antivirus software by deleting
registry keys, stopping running processes and removing
virus-definition files.

Clues in the code The worm also sports a message in its code from the
author, who brags that it only took three weeks to create the
malicious program.

The author claims the virus originated in Asia and may have bugs
because of how fast he created it.

MessageLabs' own data points to China as the source of the first
e-mails containing the worm.

By noon PST, major antivirus vendors had updated their virus
definitions to recognize the newest Klez variant. However, in most
cases, users will have to initiate an update to download the newest
definitions and be protected


Do you need to get-away?  Finance incredible vacations,
interest free, to hundreds of destinations - $3,000 travel
credit line with Guaranteed Approval! Vacations for as
little as $18/Month! 

--via http://techPolice.com
archive: http://theMezz.com/cybercrime/archive
subscribe: [EMAIL PROTECTED]
--via http://theMezz.com

This email was sent to: archive@jab.org

EASY UNSUBSCRIBE click here: http://topica.com/u/?b1dhr0.b2EDp2
Or send an email to: [EMAIL PROTECTED]

T O P I C A -- Register now to manage your mail!

Reply via email to