Submission Summary:

• Submission details:
• Submission received: 22 December 2010, 16:53:16
• Processing time: 10 min 19 sec
• Submitted sample:
• File MD5: 0xC467AE8C90AAECF6656513911617CF20
• File SHA-1: 0xBC2E7206510E5CC9A6FB1727E69B2E746D02724E
• Filesize: 47,628 bytes
• Alias:
• Email-Worm.Rontokbro!rem [PCTools]
• W32.Rontokbro@mm [Symantec]
• Email-Worm.Win32.Brontok.q [Kaspersky Lab]
• W32/Rontokbro.gen@MM [McAfee]
• W32/Brontok-BZ [Sophos]
• Email-Worm.Win32.Brontok [Ikarus]
• Win32/Brontok.worm.41996 [AhnLab]

• Summary of the findings:

What's been found	Severity Level
Hosts file modification that may block access to the security web sites.
Downloads/requests other files from Internet.
Modifies some system settings that may have negative impact on overall system security state.
Creates a startup registry entry.
Contains characteristics of an identified security risk.

Technical Details:

Possible Security Risk

• Attention! Characteristics of the following security risk was identified in the system:

Security Risk	Description
Email-Worm.Brontok.Q	Email.Worm.Brontok.Q is an email worm that propagates by sending itself to email contacts harvested from an infected machine. This worm employs several anti-removal tactics that will cause a system reboot when triggered.

• Attention! The following threat category was identified:

Threat Category	Description
	A network-aware worm that attempts to replicate across the existing network(s)

File System Modifications

• The following files were created in the system:

#	Filename(s)	File Size	File Hash	Alias
1	%AppData%\csrss.exe %AppData%\inetinfo.exe %AppData%\lsass.exe %AppData%\services.exe %AppData%\smss.exe %AppData%\winlogon.exe %Programs%\Startup\Empty.pif %Templates%\WowTumpeh.com %Windir%\eksplorasi.exe %Windir%\ShellNew\bronstab.exe [file and pathname of the sample #1] %System%\%UserName%'s Setting.scr	47,628 bytes	MD5: 0xC467AE8C90AAECF6656513911617CF20 SHA-1: 0xBC2E7206510E5CC9A6FB1727E69B2E746D02724E	Email-Worm.Rontokbro!rem [PCTools] W32.Rontokbro@mm [Symantec] Email-Worm.Win32.Brontok.q [Kaspersky Lab] W32/Rontokbro.gen@MM [McAfee] W32/Brontok-BZ [Sophos] Email-Worm.Win32.Brontok [Ikarus] Win32/Brontok.worm.41996 [AhnLab]
2	%AppData%\ListHost10.txt	12,407 bytes	MD5: 0x5C1C630852DA135D1DAB310A8CDBA280 SHA-1: 0xD5A0FF76142008F19DA82FD78879DD3EC8ED9613	(not available)
3	%Windir%\Tasks\At1.job	402 bytes	MD5: 0xA07ABED9B91D93CBF2EF35648955ABB5 SHA-1: 0xA22E1852FAE5710A0ECDEE1963F1A0AFCC8BE1CE	(not available)

• Notes:
• %AppData% is a variable that refers to the file system directory that serves as a common repository for application-specific data. A typical path is C:\Documents and Settings\[UserName]\Application Data.
• %Programs% is a variable that refers to the file system directory that contains the user's program groups. A typical path is C:\Documents and Settings\[UserName]\Start Menu\Programs.
• %Templates% is a variable that refers to the file system directory that serves as a common repository for document templates. A typical path is C:\Documents and Settings\[UserName]\Templates.
• %Windir% is a variable that refers to the Windows installation folder. By default, this is C:\Windows or C:\Winnt.
• %UserName% is a variable that refers to the current user name.

• The following file was modified:
• c:\AUTOEXEC.BAT

• The following directories were created:
• %AppData%\Bron.tok-10-22
• %Windir%\ShellNew

Memory Modifications

• There were new processes created in the system:

Process Name	Process Filename	Main Module Size
winlogon.exe	%AppData%\winlogon.exe	249,856 bytes
services.exe	%AppData%\services.exe	249,856 bytes
lsass.exe	%AppData%\lsass.exe	249,856 bytes
csrss.exe	%AppData%\csrss.exe	249,856 bytes
[filename of the sample #1]	[file and pathname of the sample #1]	249,856 bytes

Registry Modifications

• The following Registry Key was created:
• HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System

• The newly created Registry Values are:
• [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
• Bron-Spizaetus = ""%Windir%\ShellNew\bronstab.exe""

so that bronstab.exe runs every time Windows starts

• [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer]
• NoFolderOptions = 0x00000001

to remove the Folder Options item from all Windows Explorer menus and from Control Panel

• [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System]
• DisableRegistryTools = 0x00000001
• DisableCMD = 0x00000000

to disable the Windows registry editors (Regedt32.exe and Regedit.exe)

• [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run]
• Tok-Cirrhatus = ""%AppData%\smss.exe""

so that smss.exe runs every time Windows starts

• The following Registry Value was modified:
• [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
• Shell =

Other details

• The HOSTS file was updated with the following URL-to-IP mappings:

• There was registered attempt to establish connection with the remote host. The connection details are:

• The data identified by the following URLs was then requested from the remote web server:
• http://www.geocities.com/tlustabro3/BrontokInf10.txt
• http://www.geocities.com/tlustabro3/Host10.txt