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  3. W32.Mixor.C@mm

W32.Mixor.C@mm

Risk Level 2: Low

Discovered:
October 31, 2006
Updated:
February 13, 2007 1:01:53 PM
Type:
Worm, Virus
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows XP

Once executed, W32.Mixor.C@mm performs the following actions:
  1. Copies itself to the following location:

    %System%\wservice.exe

    Note: %System% is a variable that refers to the System folder. By default this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).

  2. Copies itself to all folders on local drives and mapped network drives as the following name:

    [8 RANDOM LETTERS].t (Copy of the worm)

  3. Infects .exe and .scr files in those folders. The infected files are a copy of W32.Mixor!Inf.

  4. Adds itself to .rar archives on local drives and mapped network drives as the following name:

    [7 RANDOM LETTERS].exe (Copy of the worm)

  5. Creates the following file:

    %CurrentFolder%\[7 RANDOM LETTERS].exe (Copy of Trojan.Galapopper.A)

    Note: %CurrentFolder% is a variable that refers to the folder where the risk was originally executed.

  6. Adds the value:

    "UpdateService" = "%System%\wservice.exe..."

    to the following registry subkeys:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run


    so that it runs every time Windows starts.

  7. Adds the value:

    "Start" = "4"

    to the following registry subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess

    to disable the Windows Firewall.

  8. Gathers email addresses from the Windows Address Book file by checking the file linked to the following registry subkey:

    HKEY_CURRENT_USER\Software\Microsoft\WAB\WAB4\Wab File Name

  9. Sends mail to the addresses harvested from the compromised computer, which has the following characteristics:

    Subject:
    One of the following:
    • White house news!
    • URG
    • ATTN TO EVERYBODY!
    • READ AND RESEND ASAP!
    • Incredible news!
    • NEWS!
    • ATTN
    • URGENT NEWS!

      Message body:
      One of the following:
    • 3rd Glogal War Just Started!!! Read more in file!
    • Putin and Bush starts NUCLEAR WAR! Check the file!
    • GLOBAL NUCLEAR WAR JUST STARTED! News in file.
    • Nuclear War in Russia! Read news in file!
    • Nuclear WAR in USA! Read attached file!
    • President Putin dead! Read more in attached file!
    • President Bush DEAD! Read attached file!

      Attachment:
      One of the following:
    • open.exe
    • truth.exe
    • war.exe
    • last.exe
    • about me.exe
    • a.exe
    • never.exe
    • latest news.exe
    • read me.exe

  10. Ends security-related processes, if one of the following words is included in the window title:

    • mcafee
    • taskmgr
    • hijack
    • f-pro
    • lockdown
    • msconfig
    • firewall
    • blackice
    • avg
    • vsmon
    • zonea
    • spybot
    • nod32
    • reged
    • rav
    • nav
    • avp
    • troja
    • viru
    • anti

Recommendations

Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

  • Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
  • Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
  • Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
  • Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
  • Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
  • Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
  • If a threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
  • Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
  • Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
  • Isolate compromised computers quickly to prevent threats from spreading further. Perform a forensic analysis and restore the computers using trusted media.
  • Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
  • If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
  • For further information on the terms used in this document, please refer to the Security Response glossary.
Writeup By: Chen Yu
Summary| Technical Details| Removal

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