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Virus:Worm/Koobfa.75264.D
Date discovered:07/07/2010
Type:Worm
In the wild:Yes
Reported Infections:Low to medium
Distribution Potential:Low to medium
Damage Potential:Low to medium
Static file:Yes
File size:75.264 Bytes
MD5 checksum:86ad4190c37cd92a417cf71ca8d6aafc
IVDF version:7.10.09.33 - Wednesday, July 7, 2010

 General Method of propagation:
   • Local network


Aliases:
   •  Bitdefender: Trojan.Generic.KD.8086
   •  Panda: W32/Koobface.KG.worm
   •  Eset: Win32/Koobface.NCT


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


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

 Files It copies itself to the following location:
   • %drive%\windows\bill108.exe



It overwrites the following files.
%WINDIR%\bill120.exe
%WINDIR%\bill108.exe
%WINDIR%\bk23567.dat



It deletes the initially executed copy of itself.



It deletes the following files:
   • %HOME%\Local Settings\Application Data\rdr_1281069652.exe
   • %TEMPDIR%\zpskon_1281079908.exe
   • %drive%\h.tmp
   • %TEMPDIR%\captcha.bat
   • %drive%\1.bat
   • %TEMPDIR%\zpskon_1281077066.exe
   • %drive%\3.reg
   • %malware execution directory%\SelfDel.bat



The following files are created:

%drive%\3.reg This is a non malicious text file with the following content:
   • %code that runs malware%

%malware execution directory%\df1a245s4_1284.exe Further investigation pointed out that this file is malware, too. Detected as: TR/Dropper.Gen

%TEMPDIR%\zpskon_1281078711.exe Further investigation pointed out that this file is malware, too. Detected as: BDS/Backdoor.Gen

%drive%\windows\bk23567.dat
%TEMPDIR%\zpskon_1281079908.exe Further investigation pointed out that this file is malware, too. Detected as: TR/Dropper.Gen

– %HOME%\Local Settings\Application Data\0535049569854.xxe
%TEMPDIR%\captcha.bat Furthermore it gets executed after it was fully created. This batch file is used to delete a file.
%temporary internet files%\v2captcha21[1].exe Further investigation pointed out that this file is malware, too. Detected as: TR/Spy.19456.86

%temporary internet files%\migdal.org.il[1].exe Further investigation pointed out that this file is malware, too. Detected as: TR/Dropper.Gen

%WINDIR%\dxxdv34567.bat
%drive%\h.tmp Further investigation pointed out that this file is malware, too. Detected as: TR/Qhost.2560

%malware execution directory%\SelfDel.bat Furthermore it gets executed after it was fully created. This batch file is used to delete a file.
%temporary internet files%\loader[1].exe Further investigation pointed out that this file is malware, too. Detected as: TR/Dropper.Gen

%temporary internet files%\hostsgb3[1].exe Further investigation pointed out that this file is malware, too. Detected as: TR/ATRAPS.Gen

%drive%\1.bat Furthermore it gets executed after it was fully created. This batch file is used to delete a file.
%temporary internet files%\ws[1].exe Further investigation pointed out that this file is malware, too. Detected as: BDS/Backdoor.Gen

– %HOME%\Local Settings\Application Data\01005199495648.xxe
– %HOME%\Local Settings\Application Data\rdr_1281069652.exe Further investigation pointed out that this file is malware, too. Detected as: TR/Spy.19456.86

%PROGRAM FILES%\webserver\webserver.exe Further investigation pointed out that this file is malware, too. Detected as: BDS/Backdoor.Gen

%SYSDIR%\captcha.dll Further investigation pointed out that this file is malware, too. Detected as: TR/Spy.19456.86

– %HOME%\Local Settings\Application Data\0991021011025699.xxe
%TEMPDIR%\zpskon_1281077066.exe Further investigation pointed out that this file is malware, too. Detected as: TR/ATRAPS.Gen

%SYSDIR%\drivers\etc\hosts Further investigation pointed out that this file is malware, too. Detected as: TR/Qhost.2560

%drive%\windows\bill120.exe Further investigation pointed out that this file is malware, too. Detected as: TR/Dropper.Gen




It tries to download some files:

– The location is the following:
   • http://www.usenet4all.ch/**********/?action=%character string%&v=%number%&crc=%number%


– The location is the following:
   • http://www.goo**********.com/


– The location is the following:
   • http://bushdecor.com/**********/?action=%character string%&v=%number%&crc=%number%


– The locations are the following:
   • http://lode-willems.be/**********/?action=%character string%&v=%number%&crc=%number%
   • http://lode-willems.be/**********/?action=%character string%&mode=%character string%&age=%number%&a=%character string%&v=%number%&c_fb=%number%&iedef=%number%&ie=%character string%
   • http://lode-willems.be/**********/?getexe=%character string%
   • http://lode-willems.be/**********/?getexe=%character string%
   • http://lode-willems.be/**********/?getexe=%character string%
   • http://lode-willems.be/**********/?getexe=%character string%


– The location is the following:
   • http://u07012010u.com/**********/?uptime=%number%&v=%number%&sub=%number%&ping=%number%&hits=%number%&noref=%number%&port=%number%&ftp=%number%&proxy=%number%


– The location is the following:
   • http://www.hoganjobs.com/**********/?action=%character string%&v=%number%&crc=%number%


– The location is the following:
   • http://silverbirdgroup.com/**********/?action=%character string%&v=%number%&crc=%number%


– The location is the following:
   • http://migdal.org.il/adm/**********


– The location is the following:
   • http://www.sevenpinesstables.com/**********/?getexe=%character string%


– The location is the following:
   • http://www.wttcmi.com/**********/?action=%character string%&v=%number%&crc=%number%


– The locations are the following:
   • http://www.powertreecorp.com/**********/?action=%character string%&v=%number%&crc=%number%
   • http://www.powertreecorp.com/**********/?action=%character string%&a=%character string%&v=%number%&c_fb=%number%&ie=%character string%




It tries to executes the following files:

– Filename:
   • %WINDIR%\bill108.exe


– Filename:
   • %TEMPDIR%\\zpskon_1281078711.exe


– Filename:
   • cmd /c SelfDel.bat


– Filename:
   • reg add HKLM\Software\Microsoft\Windows\CurrentVersion /v Port /t REG_DWORD /d 237


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


– Filename:
   • netsh firewall add portopening TCP 237 webserver ENABLE


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


– Filename:
   • "%HOME%\Local Settings\Application Data\rdr_1281069652.exe"


– Filename:
   • cmd /c "%HOME%\Local Settings\Application Data\rdr_1281069652.exe" /res >%temp%\captcha.bat


– Filename:
   • "%HOME%\Local Settings\Application Data\rdr_1281069652.exe" /res


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


– Filename:
   • cmd /c %WINDIR%\dxxdv34567.bat


– Filename:
   • cmd /c "%temp%\captcha.bat"


– Filename:
   • netsh firewall add allowedprogram name="captcha" program="%SYSDIR%\svchost.exe" mode=ENABLE


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


– Filename:
   • sc create "captcha" type= share start= auto binPath= "%SYSDIR%\svchost.exe -k captcha"


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


– Filename:
   • sc start "webserver"


– Filename:
   • reg add "HKLM\SYSTEM\CurrentControlSet\Services\captcha\parameters" /v ServiceDll /t REG_EXPAND_SZ /d "%SYSDIR%\captcha.dll" /f


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


– Filename:
   • reg add "HKLM\SYSTEM\CurrentControlSet\Services\captcha" /v Type /t REG_DWORD /d 288 /f


– Filename:
   • reg add "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\svchost" /v captcha /t REG_MULTI_SZ /d "captcha\0" /f


– Filename:
   • df1a245s4_1284.exe


– Filename:
   • rundll32 captcha,ServiceMain


– Filename:
   • %malware execution directory%\df1a245s4_1284.exe


– Filename:
   • %WINDIR%\bill120.exe


– Filename:
   • regedit /s c:\2.reg


– Filename:
   • %TEMPDIR%\\zpskon_1281077066.exe


– Filename:
   • cmd /c c:\1.bat


– Filename:
   • %TEMPDIR%\\zpskon_1281079908.exe


– Filename:
   • %TEMPDIR%\zpskon_1281079908.exe

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

– [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   • "sysfbtray"="%WINDIR%\bill120.exe"



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

– [HKLM\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\
   FirewallPolicy\StandardProfile\GloballyOpenPorts\List]
   • "237:TCP"="237:TCP:*:Enabled:webserver"
   • "4000:TCP"="4000:TCP:*:Enabled:webserver"
   • "53:TCP"="53:TCP:*:Enabled:webserver"



The following registry keys are added:

– [HKCU\Software\Microsoft\Internet Explorer\Main]
   • "tp"="1000"

– [HKLM\SYSTEM\CurrentControlSet\Services\webserver]
   • "FailureActions"=hex:b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x14\x00\x00\x00\x01\x00\x00\x00`\xea\x00\x00\x01\x00\x00\x00`\xea\x00\x00\x01\x00\x00\x00`\xea\x00\x00'

– [HKLM\SYSTEM\CurrentControlSet\Services\captcha]
   • "FailureActions"=hex:b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x14\x00\x00\x00\x01\x00\x00\x00`\xea\x00\x00\x01\x00\x00\x00`\xea\x00\x00\x01\x00\x00\x00`\xea\x00\x00'

– [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SvcHost]
   • "captcha"="captcha"

– [HKLM\SOFTWARE\Policies\Microsoft\Windows Defender]
   • "DisableAntiSpyware"=dword:0x00000001

– [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Tracing\
   Microsoft\NAP\Netsh]
   • "Active"=dword:0x00000001
   • "ControlFlags"=dword:0x00000001
   • "LogSessionName"="stdout"

– [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Tracing\
   Microsoft\NAP\Netsh\Napmontr]
   • "BitNames"=" NAP_TRACE_BASE NAP_TRACE_NETSH"
   • "Guid"="710adbf0-ce88-40b4-a50d-231ada6593f0"

– [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion]
   • "Port"=dword:0x000000ed

– [HKLM\SYSTEM\CurrentControlSet\Services\captcha\parameters]
   • "ServiceDll"="%SYSDIR%\captcha.dll"



The following registry key is changed:

– [HKLM\SYSTEM\CurrentControlSet\Services\captcha]
   New value:
   • "Type"=dword:0x00000120

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


Exploit:
It makes use of the following Exploit:
– MS04-007 (ASN.1 Vulnerability)

 Hosts The host file is modified as explained:

– Access to the following domain is redirected to another destination:
   • 85.13.206.115 u07012010u.com


Description inserted by Petre Galan on Friday, August 6, 2010
Description updated by Petre Galan on Friday, August 6, 2010

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