Virus:Worm/Sohanat.AX
Date discovered:14/02/2007
Type:Worm
In the wild:Yes
Reported Infections:Low
Distribution Potential:Low
Damage Potential:Medium
Static file:Yes
File size:185.542 Bytes
MD5 checksum:019491172aa082ca33a76793a651a09a
VDF version:6.37.01.105
IVDF version:6.37.01.106 - Friday, February 16, 2007

 General Method of propagation:
   • Messenger


Aliases:
   •  F-Secure: IM-Worm.Win32.Sohanad.u
   •  Sophos: W32/Sohana-K
   •  Grisoft: Autoit.Y
   •  Eset: Win32/Sohanad.U


Platforms / OS:
   • Windows 95
   • Windows 98
   • Windows 98 SE
   • Windows NT
   • Windows ME
   • Windows 2000
   • Windows XP
   • Windows 2003


Side effects:
   • Disable security applications
   • Downloads a malicious file
   • Drops a malicious file
   • Registry modification

 Files It tries to download a file:

– The location is the following:
   • http://64.26.25.75/**********
It is saved on the local hard drive under: %WINDIR%\svchost.exe Furthermore this file gets executed after it was fully downloaded. Further investigation pointed out that this file is malware, too. Detected as: Worm/VB.CK.9

 Registry The following registry key is added in order to run the process after reboot:

– [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   • "SVCHOST"="%WINDIR%\svchost.exe"
   • "Task Manager"="%WINDIR%\svhost32.exe"



The following registry keys are added:

– [HKLM\SOFTWARE\Policies\Microsoft\Windows NT\SystemRestore]
   • "DisableConfig"="1"

– [HKCU\Software\Google\GoogleToolbarNotifier]
   • "KeepDS"=dword:00000000
   • "ShowTrayIcon"=dword:00000000

– [HKCU\Software\Yahoo\pager\View\YMSGR_Launchcast]
   • "content url"="http://zinblog.com"

– [HKCU\Software\Yahoo\pager\View\YMSGR_buzz]
   • "content url"="http://zinblog.com"

– [HKCU\Software\Policies\Microsoft\Internet Explorer\Control Panel]
   • "Homepage"=dword:00000001



The following registry keys are changed:

Internet Explorer's start page:
– [HKCU\Software\Microsoft\Internet Explorer\Main]
   New value:
   • "Start Page"="http://zinblog.com"

– [HKCU\Software\Microsoft\Internet Explorer\Main]
   New value:
   • "Search Bar"="http://zinblog.com"
   • "Use Search Asst"="no"
   • "Search Page"="http://zinblog.com"

– [HKCU\Software\Microsoft\Internet Explorer\SearchUrl]
   New value:
   • "(Default)"="http://zinblog.com"

– [HKCU\Software\Microsoft\Search Assistant]
   New value:
   • "DefaultSearchURL"="http://zinblog.com"

Various Explorer settings:
– [HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer]
   New value:
   • "NoRun"=dword:00000001

Disable Regedit and Task Manager:
– [HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System]
   New value:
   • "DisableRegistryTools"=dword:00000001
   • "DisableTaskMgr"=dword:00000001

 Messenger – Yahoo Messenger
All entries in the contact list.


Message
The sent message looks like one of the following:

   • This is my one-off Xmas e-card for you ^_^ http://zinblog.com/?id=ecard =)) This message was certified by %yahoo user%

   • making money online never be easier : http://unitedreporters.org/?id=tips >:D< This message was certified by %yahoo user%, no worm

   • Vote for our Miss beauty today !!! http://unitedreporters.org/?id=miss_world :x:x:x:x:x This message was certified by %yahoo user%, no worm

   • DIY dynamite from Whisky, Coke and Mentos : http://zinblog.com/?id=dynamite << This message was certified by %yahoo user%, no worm

   • Fuck !!! X-( http://zinblog.com/?id=password << This message was certified by %yahoo user%, no worm

   • I made 10 gifts for the first 10 people post comments on my own page : http://lucyblog.com ^_^

   • Be careful. There’ll be earthquake tonight !!! http://unitedreporters.org/?id=warning << This message was certified by %yahoo user%, no worm

   • My new personal website : http://zinblog.com c0ol !!!

   • Microsoft to release 2007 free-of-charge packs of Winsdows Vista for its first 2007 online registered users: http://unitedreporters.org/?id=ms << This message was certified by %yahoo user%, no worm

   • wtf is this ? wanna give me a shit ? http://unitedreporters.org/?id=news X-(

   • Breaking news : Osama Bin Laden has been arrested !! http://unitedreporters.org/?news_id=18388 This message was certified by %yahoo user%, no worm

   • Yahoo to charge fee for its YM service http://zinblog.com/?id=ym This message was certified by %yahoo user%, no worm

   • OMG ! She is really beautiful :x http://zinblog.com/DSC00273.JPG This message was certified by %yahoo user%, no worm

The URL then refers to a copy of the described malware. If the user downloads and executes this file the infection process will start again.


The received messages may look like the following:



 File details Programming language:
 The malware program was written in MS Visual C++.
In order to aggravate detection and reduce size of the file it is packed with the following runtime packer:
   • UPX

Description inserted by Ernest Szocs on Thursday, February 15, 2007
Description updated by Ernest Szocs on Monday, February 19, 2007

Back . . . .