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Date discovered:02/08/2010
In the wild:Yes
Reported Infections:Low to medium
Distribution Potential:Low
Damage Potential:Medium
Static file:Yes
File size:13.824 Bytes
MD5 checksum:89ce444593ac67ab669768c2160fc4ee
IVDF version:

 General Aliases:
   •  Bitdefender: Trojan.Agent.21307
   •  Panda: W32/Koobface.KG.worm
   •  Eset: Win32/TrojanProxy.Small.NEB

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

Side effects:
   • Downloads a malicious file
   • Drops malicious files
   • Registry modification

 Files It copies itself to the following location:
   • %PROGRAM FILES%\webserver\webserver.exe

It tries to download a file:

– The location is the following:

It tries to execute the following files:

– Filename:
   • reg add HKLM\Software\Microsoft\Windows\CurrentVersion /v Port /t REG_DWORD /d 1034

– Filename:
   • netsh add allowedprogram "%PROGRAM FILES%\webserver\webserver.exe" webserver ENABLE

– Filename:
   • netsh firewall add portopening TCP 1034 webserver ENABLE

– Filename:
   • netsh firewall add portopening TCP 4000 webserver ENABLE

– Filename:
   • netsh firewall add portopening TCP 53 webserver ENABLE

– Filename:
   • sc create "webserver" binPath= "%PROGRAM FILES%\webserver\webserver.exe" type= share start= auto

– Filename:
   • reg add "HKLM\SYSTEM\CurrentControlSet\Services\webserver" /v FailureActions /t REG_BINARY /d 00000000000000000000000003000000140000000100000060EA00000100000060EA00000100000060EA0000 /f

– Filename:
   • sc start "webserver"

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

– [HKLM\SYSTEM\CurrentControlSet\Services\webserver]
   • "ErrorControl"=dword:0x00000001
   • "ImagePath"="%PROGRAM FILES%\webserver\webserver.exe"
   • "ObjectName"="LocalSystem"
   • "Start"=dword:0x00000002
   • "Type"=dword:0x00000020

It creates the following entry in order to bypass the Windows XP firewall:

– [HKLM\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\
   • "1034:TCP"="1034:TCP:*:Enabled:webserver"
   • "4000:TCP"="4000:TCP:*:Enabled:webserver"
   • "53:TCP"="53:TCP:*:Enabled:webserver"

The following registry key is added:

– [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion]
   • "Port"=dword:0x00000344

 Backdoor The following port is opened:

%PROGRAM FILES%\webserver\webserver.exe on TCP port 1034

 File details Runtime packer:
In order to aggravate detection and reduce size of the file it is packed with a runtime packer.

Description inserted by Petre Galan on Wednesday, September 22, 2010
Description updated by Petre Galan on Friday, September 24, 2010

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