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Virus:Worm/Sdbot.39936.13
Date discovered:12/08/2006
Type:Worm
In the wild:Yes
Reported Infections:Low
Distribution Potential:Medium
Damage Potential:Medium
Static file:Yes
File size:39.936 Bytes
MD5 checksum:EDECDE54249650429D8BDFD1DB6B3B27
VDF version:6.35.01.84 - Saturday, August 12, 2006
IVDF version:6.35.01.84 - Saturday, August 12, 2006

 General Method of propagation:
   • Local network


Aliases:
   •  Symantec: W32.Spybot.Worm
   •  Sophos: W32/Sdbot-BND
   •  VirusBuster: Worm.SdBot.CQJ
   •  Eset: IRC/SdBot


Platforms / OS:
   • Windows NT
   • Windows ME
   • Windows 2000
   • Windows XP
   • Windows 2003


Side effects:
   • Disable security applications
   • Registry modification
   • Makes use of software vulnerability
   • Steals information
   • Third party control

 Files It copies itself to the following location:
   • %WINDIR%\svchostwin32

 Registry The following registry keys are added in order to load the service after reboot:

– [HKLM\SYSTEM\CurrentControlSet\Services\SVCWin32Update]
   • "Type"=dword:00000110
   • "Start"=dword:00000002
   • "ErrorControl"=dword:00000000
   • "ImagePath"=hex(2):%WINDIR%\svchostwin32
   • "DisplayName"="Win32 Network Update"
   • "ObjectName"="LocalSystem"
   • "FailureActions"=hex:%hex values%
   • "Description"="SVCWin32 Update"

– [HKLM\SYSTEM\CurrentControlSet\Services\SVCWin32Update\Enum]
   • "0"="Root\\LEGACY_SVCWIN32UPDATE\\0000"
   • "Count"=dword:00000001
   • "NextInstance"=dword:00000001

– [HKLM\SYSTEM\CurrentControlSet\Services\SVCWin32Update\Security]
   • "Security"=hex:%hex values%



The following registry keys are changed:

– [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\
   Auto Update]
   Old value:
   • "AUOptions"=%user defined settings%
   New value:
   • "AUOptions"=dword:00000001

– [HKLM\SOFTWARE\Policies\Microsoft\WindowsFirewall\DomainProfile]
   Old value:
   • "EnableFirewall"=%user defined settings%
   New value:
   • "EnableFirewall"=dword:00000000

– [HKLM\SOFTWARE\Policies\Microsoft\WindowsFirewall\StandardProfile]
   Old value:
   • "EnableFirewall"=%user defined settings%
   New value:
   • "EnableFirewall"=dword:00000000

– [HKLM\SOFTWARE\Microsoft\Security Center]
   Old value:
   • "UpdatesDisableNotify"=%user defined settings%
   • "AntiVirusDisableNotify"=%user defined settings%
   • "FirewallDisableNotify"=%user defined settings%
   • "AntiVirusOverride"=%user defined settings%
   • "FirewallOverride"=%user defined settings%
   New value:
   • "UpdatesDisableNotify"=dword:00000001
   • "AntiVirusDisableNotify"=dword:00000001
   • "FirewallDisableNotify"=dword:00000001
   • "AntiVirusOverride"=dword:00000001
   • "FirewallOverride"=dword:00000001

– [HKLM\SYSTEM\CurrentControlSet\Control\Lsa]
   Old value:
   • "restrictanonymous"=%user defined settings%
   New value:
   • "restrictanonymous"=dword:00000001

– [HKLM\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters]
   Old value:
   • "AutoShareWks"=%user defined settings%
   • "AutoShareServer"=%user defined settings%
   New value:
   • "AutoShareWks"=dword:00000000
   • "AutoShareServer"=dword:00000000

– [HKLM\SYSTEM\CurrentControlSet\Services\lanmanworkstation\
   parameters]
   Old value:
   • "AutoShareWks"=%user defined settings%
   • "AutoShareServer"=%user defined settings%
   New value:
   • "AutoShareWks"=dword:00000000
   • "AutoShareServer"dword:00000000

– [HKLM\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate]
   Old value:
   • "DoNotAllowXPSP2"=%user defined settings%
   New value:
   • "DoNotAllowXPSP2"=dword:00000001

– [HKLM\Software\Microsoft\OLE]
   Old value:
   • "EnableDCOM"=%user defined settings%
   New value:
   • "EnableDCOM"="N"

– [HKLM\SYSTEM\CurrentControlSet\Control]
   Old value:
   • "WaitToKillServiceTimeout"=%user defined settings%
   New value:
   • "WaitToKillServiceTimeout"="7000"

 Network Infection In order to ensure its propagation the malware attemps to connect to other machines as described below.

It drops copies of itself to the following network shares:
   • C$
   • ADMIN$
   • IPC$
   • %all shared folders%


Exploit:
It makes use of the following Exploits:
– MS03-039 (Buffer Overrun in RPCSS Service)
– MS03-049 (Buffer Overrun in the Workstation Service)
– MS04-007 (ASN.1 Vulnerability)
– MS05-039 (Vulnerability in Plug and Play)


IP address generation:
It creates random IP addresses and tries to establish a connection with them.


Infection process:
Creates an FTP script on the compromised machine in order to download the malware to the remote location.
The downloaded file is stored on the compromised machine as: %SYSDIR%\eraseme_%number%.exe


Remote execution:
–It attempts to schedule a remote execution of the malware, on the newly infected machine. Therefore it uses the NetScheduleJobAdd function.

 IRC To deliver system information and to provide remote control it connects to the following IRC Servers:

Server: free.backendportal.**********
Port: 8080
Channel: #prom
Nickname: [P00|USA|%random character string%]
Password: tru00

Server: win32.onlinewebportal.**********
Port: 8080
Channel: #prom
Nickname: [P00|USA|%random character string%]
Password: tru00

Server: free.backendportal.**********
Port: 8080
Channel: #prom
Nickname: [P00|USA|%random character string%]
Password: tru00

Server: free.avupdates.**********
Port: 8080
Channel: #prom
Nickname: [P00|USA|%random character string%]
Password: tru00



– This malware has the ability to collect and send information such as:
    • Malware uptime
    • Information about the network
    • Information about running processes


– Furthermore it has the ability to perform actions such as:
    • Disable network shares
    • Download file
    • Enable network shares
    • Execute file
    • Join IRC channel
    • Kill process
    • Perform network scan
    • Shut down system
    • Start spreading routine
    • Updates itself

 Process termination  List of services that are disabled:
   • Windows Firewall/ICS
   • Security Center
   • Messenger
   • Remote Registry
   • Telnet

 Miscellaneous Mutex:
It creates the following Mutex:
   • Multiply NetAssets


Anti debugging
It checks if the following program is running:
   • SoftIce


 File details Programming language:
The malware program was written in MS Visual C++.


Runtime packer:
In order to aggravate detection and reduce size of the file it is packed with the following runtime packer:
   • UPX

Description inserted by Iulia Diaconescu on Wednesday, October 25, 2006
Description updated by Iulia Diaconescu on Monday, November 6, 2006

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