Home / malware Worm:W32/Somali.A
First posted on 13 July 2010.
Source: SecurityHomeAliases :
There are no other names known for Worm:W32/Somali.A.
Explanation :
A standalone malicious program which uses computer or network resources to make complete copies of itself. May include code or other malware to damage both the system and the network.
Additional DetailsSomali.A is a mass-mailing worm that terminates security-related processes and blocks antivirus-related software updates.
Somali.A is also capable of opening a port on the infected machine. If a remote user sends strings to the opened port, the worm is able to reply to the remote user.
This malware will only run on Windows platforms that have .NET framework installed.
Execution
Upon execution, Somali.A modifies the registry so that the worm is executed every time a user logs on.
It then drops several copies of itself:
€ %windir%\system32\ctfmon32.exe € %rootdir%\project.pif € %currentdir%\Project-setup.exe
The worm also displays the following fake error messages:
Note: This message will appear on the first run on a clean machine.
Note: This message will appear if it has been run previously.
Propagation
Somali.A can also propagate through network. It does this by creating a Shared folder:
€ %rootdir%\System33
And then dropping a copy of itself on the shared folder as Sound.exe.
The said shared folder has a share name of MadSoli, as seen in the screenshot below:
Subsequently, it will create the following registry key:
€ [HKLM\System\CurrentControlSet\Services\lanmanserver\Shares]
MadSoli = {Multi-String} - See Screenshot:
Somali.A attempts to mass-mail itself using mx4.mail.yahoo.com as its SMTP server.
It searches for Yahoo! e-mail addresses on Windows folder in the files with the following extension names:
€
adb
€
asp
€
cfg
€
cgi
€
dbx
€
eml
€
html
€
pl
€
shtm
€
txt
€
wab
€
xml
Possible Email address of the Sender:
€
antiblaster@yahoo.com
€
avg@yahoo.com
€
bill@yahoo.com
€
bob@yahoo.com
€
ebook@yahoo.com
€
info@yahoo.com
€
iraq@yahoo.com
€
LongShot@yahoo.com
€
matt@yahoo.com
€
mcafee@yahoo.com
€
nod32@yahoo.com
€
panda@yahoo.com
€
smith@yahoo.com
€
stan@yahoo.com
€
steve@yahoo.com
€
symantec@yahoo.com
€
update@yahoo.com
€
YourFriend@yahoo.com
€
CC: software@yahoo.com
€
BCC: crack@yahoo.com
Possible Subjects:
€ Announcement € ANTI VIRUS € Attention € E-mail account disabling warning € FBI € IranSare2008 € mcafee € NOD32 € password € Read it immediately € Soccer funs in public place € symantec € Text Message € Text message € Yahoo! € Your IP was logged
Possible Message Body:
€
Your e-mail account was used to send a huge amount of unsolicited spam messages during the recent week. If you could please take 5-10 minutes out of your online experiences and confirm the attach document so you will not run into any future problems with the online service.
€ It has come to our attention that your (File!) User Profile ( x )records are out of date. For further details see the attached document. Tank you for using ! € Thank you for using file € +++ Attachment: No Virus (Clean) € +++[mcafee] Antivirus - www.mcafee.com € Deliver Error € Message Error € help attached € such as yours € illegal st. of you € I have your password! € classroom test of you? € old photos about you?
Payload
Somali.A checks the running processes and terminates processes with the following strings:
€ AVGSERV € AVGSERV9 € Clshield € DAP € GhostTray € mghtml € NAVW32 € notepad € NTPROTECTED € regedit € scan32 € SCAN95 € taskmgr
The worm creates the following user in the local User Group:
€ User name: NewAdmin
Password: MadSoli
Comment: Windows pc
Note: Run the following command from the CMD prompt to check for the said user:
€ "net user NewAdmin".
It also deletes all the subkeys on the following registry key:
€ [HKCU\Printers]
Somali.A displays the following Message Box every 19th of the month:
The worm also creates a HOST file named HOST.file in the %windir%\system32\drivers\etc directory. This HOST file will not allow accesses to the following sites:
€
avg.com
€
download.mcafee.com
€
google.com
€
google.com
€
mcafee.com
€
pandasoftware.com
€
symantec.com
€
trendmicro.com
€
update.symantec.com
€
www.24-7-transportation.com
€
www.adhdtests.com
€
www.aegee.org
€
www.aimcenter.net
€
www.alupass.lu
€
www.amanit.ru
€
www.AmirCivil.com
€
www.andara.com
€
www.angelartsanctuary.com
€
www.anthonyflanagan.com
€
www.approved1stmortgage.com
€
www.argontech.net
€
www.asianfestival.nl
€
www.atlantisteste.hpg.com.br
€
www.avg.com
€
www.avg.com
€
www.aviation-center.de
€
www.bbc.com
€
www.bbsh.org
€
www.bga-gsm.ru
€
www.boneheadmusic.com
€
www.bottombouncer.com
€
www.bradster.com
€
www.buddyboymusic.com
€
www.bueroservice-it.de
€
www.calderwoodinn.com
€
www.capri-frames.de
€
www.celula.com.mx
€
www.ceskyhosting.cz
€
www.chinasenfa.com
€
www.cntv.info
€
www.compsolutionstore.com
€
www.coolfreepages.com
€
www.corpsite.com
€
www.couponcapital.net
€
www.cpc.adv.br
€
www.crystalrose.ca
€
www.cscliberec.cz
€
www.curtmarsh.com
€
www.customloyal.com
€
www.DarrkSydebaby.com
€
www.deadrobot.com
€
www.dontbeaweekendparent.com
€
www.download.mcafee.com
€
www.dragcar.com
€
www.ecofotos.com.br
€
www.eurostavba.sk
€
www.everett.wednet.edu
€
www.fcpages.com
€
www.featech.com
€
www.FritoPie.NET
€
www.google.com
€
www.mcafee.com
€
www.microsoft.com
€
www.my-etrust.com
€
www.pandasoftware.com
€
www.symantec.com
€
www.trendmicro.com
€
www.update.symantec.com
€
www.viruslist.com
€
www.yahoo.com
€
yahoo.com
Backdoor
Somali.A opens TCP port 8051. If a remote hacker connects to the said port and sends strings through this port, Somali.A will reply with the same string with all capital letters and adds exclamation mark at the end of the string.
Registry
Somali.A creates the following auto-run registry key so that every time the user logs on, Somali.A will be executed:
€ [HKCU\Software\Microsoft\Windows\Currentversion\Run]
Services32.bak = %windi%\system32\ctfmon32.exe
For its signature, it creates the following registry key:
€ [HKCU\MadSoli]
MadSoli = "System"
It creates a Mutex named MadSoli so that there will be only one instance of itself in the memory.
Detection
F-Secure Anti-Virus detects this malware with the following updates:
[FSAV_Database_Version]
Version = 2006-08-28_04Last update 13 July 2010
