The worm's file is a Windows PE (portable executable) file about 27 kb long. The file is packed with UPX file compressor and UPX text strings in the body of the worm are replaced with dots probably by the worm's author. Worm's files usually have random data (garbage) in the end, the length and content of that area is different in different samples. The worm has most of its text strings encrypted with a simple crypto algorithm.
When the worm's file is started on a clean system and its file has SCR extension, it may display a messagebox or/and a videoeffect.
The worm usually installs itself with random name to C:\Recycler or C:\Recycled folder or, if these folders are not available, into Windows directory. Then the worm modifies default EXE file startup key [HKCR\exefile\shell\open\command]
to make itself run every time an EXE program is started. Also one of the threads of the worm continuosly refreshes this key to prevent its modification by computer user or by disinfection utility. The same thread tries to kill Windows Task Manager process.
The worm doesn't start when launched from Internet Explorer cache folder (folder containing CONTENT.IE5 string). If the worm is started from MSTASKMON.EXE file, it adds execution string for this file into WIN.INI to be started every time Windows runs. The worm starts itself as a service process, so its task is not visible in Task Manager under Windows 9x systems.
The worm loads Windows Address Book into memory, reads .NET Messenger data, Yahoo! Messenger profiles, ICQ data files, HTML, DOC and TXT files in cache folders, desktop and personal folders and stores e-mail addresses it could find there into a DLL file with a random name in Windows folder.
The worm creates a file named KITKAT in a temporary folder and writes its BASE64-encoded file data there. That file will be different from the original worm sample as the worm adds random data to its end (from MUNCH file that it generates and then deletes). The length of random data area differs every time. This technique was supposed to fool some anti-virus scanners that use CRC to detect standalone malware.
The worm spreads itself as an attachment with different names in e-mail messages with different subjects and bodies, the message composition routine is really complex. The worm uses a set of pre-defined smtp server names, message bodies, subjects, attachment names and extensions and selects them randomly to compose an e-mail message that it will send to all found e-mail addresses. It can send different types of e-mails, similar to Klez worms e-mails. The worm may or may not include IFrame exploit into the message that it sends out.
The subject of infected e-mail can be one of the following messages or a combination of them:
searching for true Love
you care ur friend
Who is ur Best Friend
make ur friend happy
True Love
Dont wait for long time
Free Screen saver
Friendship Screen saver
Looking for Friendship
Need a friend?
Find a good friend
Best Friends
I am For u
Life for enjoyment
Nothink to worryy
Ur My Best Friend
Say 'I Like You' To ur friend
Easy Way to revel ur love
Wowwwwwwwwwww check it
Send This to everybody u like
Enjoy Romantic life
Let's Dance and forget pains
war Againest Loneliness
How sweet this Screen saver
Let's Laugh
One Way to Love
Learn How To Love
Are you looking for Love
love speaks from the heart
Enjoy friendship
Shake it baby
Shake ur friends
One Hackers Love
Origin of Friendship
The world of lovers
The world of Friendship
Check ur friends Circle
Friendship
how are you
U r the person?
U realy Want this
Also the worm can compose the sublect from 2 or more different parts with or without 'Fw:' prefix:
Romantic
humour
NewWonderfool
excite
Cool
charming
Idiot
Nice
Bullsh*t
One
Funny
Great
LoveGangs
Shaking
powful
Joke
Interesting
Screensaver
Friendship
Love
relations
stuff
to ur friends
to ur lovers
for you
to see
to check
to watch
to enjoy
to share
:-)
!
!!
For example the subject of an infected message can be 'Cool stuff to see' or 'FW: Nice Screensaver for you !!'. There can be 'Fw:' prefix to the subject.
The infected message body can contain one of the following strings or blocks of strings:
Check the attachment
See the attachement
Enjoy the attachement
More details attached
Hi
Check the Attachement ..
See u
Hi
Check the Attachement ..
Attached one Gift for u..
wOW CHECK THIS
Then there can follow a fake undeliverable message report or a fake screensaver subscription message. In case the worm sends a fake bounced message, it looks like that:
This message was created automatically by mail delivery software (Exim).
A message that you sent could not be delivered to one or more of its recipients.
This is a permanent error. The following address(es) failed: [sender's e-mail address]
For further assistance, please contact [postmaster's e-mail address]
If you do so, please include this problem report. You can
delete your own text from the message returned below.
Copy of your message, including all the headers is attached
Then there goes an EML file attachment with random name that contains the worm's sample and usually IFrame exploit to make the attachment run automatically on unpatched e-mail clients.
In case the worm spreads itself with a fake screensaver subscription message, it looks like that:
This e-mail is never sent unsolicited. If you need to unsubscribe,
follow the instructions at the bottom of the message.
***********************************************************
Enjoy this friendship Screen Saver and Check ur friends circle...
Send this screensaver from [constructed URL] to everyone you
consider a FRIEND, even if it means sending it back to the person
who sent it to you. If it comes back to you, then you'll know you
have a circle of friends.
* To remove yourself from this mailing list, point your browser to:
[constructed URL]
* Enter your email address ([sender's e-mail address]) in
the field provided and click "Unsubscribe".
OR...
* Reply to this message with the word "REMOVE" in the subject line.
This message was sent to address [sender's e-mail address]
X-PMG-Recipient: [sender's e-mail address]
<>>> <>>> <>>> <>>> <>>> <>>> <>>> <>>> <>>> <>>>
In this case the worm spreads itself with one of the below given names and only SCR extension:
screensaver
screensaver4u
screensaver4u
screensaverforu
freescreensaver
love
lovers
lovescr
loverscreensaver
loversgang
loveshore
love4u
lovers
enjoylove
sharelove
shareit
checkfriends
urfriend
friendscircle
friendship
friends
friendscr
friends
friends4u
friendship4u
friendshipbird
friendshipforu
friendsworld
werfriends
passion
bullshitscr
shakeit
shakescr
shakinglove
shakingfriendship
passionup
rishtha
greetings
lovegreetings
friendsgreetings
friendsearch
lovefinder
truefriends
truelovers
f*cker
The worm also spreads itself as an attachment with double extension and with one of the following names or with a random name:
loveletter
resume
biodata
dailyreport
mountan
goldfish
weeklyreport
report
love
The first extension of the attachment can be:
doc
mp3
xls
wav
txt
jpg
gif
dat
bmp
htm
mpg
mdb
zip
The second (last) extension of the infected attachment can be:
pif
bat
scr
For example the worm's attachment name can be GOLDFISH.MPG.PIF or BIODATA.DOC.SCR. The attachment content type that the worm uses can be one of the following:
audio/x-midi
audio/x-wav
The worm has network spreading capabilities. One of the threads constantly looks for open shares and searches directories with the following names there:
WINXP
WINME
WIN
WINNT
WIN95
WIN98
WINDOWS
When the worm finds a directory with any of the above mentioned names, it tries to find WIN.INI file in that directory. If it can find such a file, the worm copies itself as MSTASKMON.EXE file into the same directory and modifies WIN.INI file on remote system to start itself there after next reboot. It should be noted that this functionality will only work under Windows 9x systems as WIN.INI file is not used by NT-based systems. But the worm can be activated on remote NT-based system if a user runs MSTASKMON.EXE file there.
One of worm's threads from time to time tries to connect to a 'www.pak.gov.pk' (government of Pakistan?) website. If the worm is widespread, this can cause a DoS (Denial of Service) attack on that webserver.
The worm looks for and terminates the processes that have the following strings in their names:
PCCIOMON
PCCMAIN
POP3TRAP
WEBTRAP
AVCONSOL
AVSYNMGR
VSHWIN32
VSSTAT
NAVAPW32
NAVW32
NMAIN
LUALL
LUCOMSERVER
IAMAPP
ATRACK
NISSERV
RESCUE32
SYMPROXYSVC
NISUM
NAVAPSVC
NAVLU32
NAVRUNR
NAVWNT
PVIEW95
F-STOPW
F-PROT95
PCCWIN98
IOMON98
FP-WIN
NVC95
NORTON
MCAFEE
ANTIVIR
WEBSCANX
SAFEWEB
ICMON
CFINET
CFINET32
AVP.EXE
LOCKDOWN2000
AVP32
ZONEALARM
WINK
SIRC32
SCAM32
So the worm not only kills tasks of anti-virus and security software, it also kills tasks of Klez and Sircam worms. The worm has different process killing routines for different types of operating systems. The worm doesn't allow programs with the above mentioned strings in their names to start on an infected system. The worm also looks for and terminates the Windows Task Manager process.
The worm creates the TXT file with random name in Windows directory with the following text:
<<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>>
iNDian sNakes pResents yAha.E
iNDian hACkers,Vxers c0me & w0Rk wITh uS & f*Ck tHE GFORCE-pAK sh*tes
bY
sNAkeeYes,c0Bra
<<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>> <<<>>>
|
