Discovered: January 17, 2006
Updated: February 13, 2007 12:50:39 PM
Also Known As: CME-24, Win32.Blackmal.F [Computer Ass, Email-Worm.Win32.Nyxem.e [F-Se, Email-Worm.Win32.Nyxem.e [Kasp, W32/MyWife.d@MM [McAfee], W32/MyWife.d@MM!M24 [McAfee], Win32/Mywife.E@mm [Microsoft], W32/Small.KI@mm [Norman], Tearec.A [Panda Software], W32/Nyxem-D [Sophos], WORM_GREW.{A, B} [Trend Micro]
Type: Worm
Systems Affected: Windows

W32.Blackmal.E@mm is a mass-mailing worm that attempts to spread through network shares and lower security settings. On the third day of every month it attempts to rewrite files with certain extensions with custom text.

High level detection - Here are some symptoms that may help determine the presence of W32.Blackmal.E@mm.

  1. Uses its own SMTP engine to send an email with a copy of itself as an attachment.

    Look for non-mail server machines sending port 25 traffic

  2. Enumerates the computers in the same domain as the host computer by using WNetOpenEnum. The worm then executes the command "net use \\[COMPUTER NAME] /user:administrator """ to connect to that computer. However, if the user on the compromised computer is already connected to some other network computer, the worm will be able to use that connection.

    Look for locked user accounts due to brute password attacks

  3. Attempts to access the following URL: [http://][REMOVED]/Count.cgi?df=765247

    Look for any computer that accessed this website. Isolate and use the repair tool or scan with updated defs

Antivirus Protection Dates

  • Initial Rapid Release version January 17, 2006
  • Latest Rapid Release version July 09, 2019 revision 021
  • Initial Daily Certified version January 17, 2006
  • Latest Daily Certified version July 10, 2019 revision 001
  • Initial Weekly Certified release date January 17, 2006

Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Technical Description

When W32.Blackmal.E@mm is executed, it performs the following actions:

  1. Copies itself as one of the following files:

    • %Windir%\Rundll16.exe
    • %System%\WINZIP_TMP.EXE
    • %System%\SAMPLE.ZIP
    • %System%\New WinZip File.exe
    • movies.exe
    • Zipped Files.exe

    • %Windir% is a variable that refers to the Windows installation folder. By default, this is C:\Windows or C:\Winnt.
    • %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 as one of the following files:

    • %System%\scanregw.exe
    • %System%\Winzip.exe
    • %System%\Update.exe

      Note: The worm monitors the above files and will recreate them if they are deleted.

  3. Creates an empty .zip file using the same file name as the worm itself in the %System% folder. It then opens this file in order to hide its functionality.

  4. Drops the file %System%\MSWINSCK.OCX which is a clean Microsoft control used for network connectivity.

  5. Adds the value:

    "ScanRegistry" = "scanregw.exe /scan"

    to the following registry subkey:


    so that it runs every time Windows starts.

    Note: The worm monitors the above registry entry and recreates it if it is deleted.

  6. Modifies the values:

    "WebView" = "0"
    "ShowSuperHidden" = "0"

    in the registry subkey:


    Note: The worm monitors the above registry entries and recreates them if they are deleted.

  7. Modifies the value:

    "FullPath" = "1"

    in the registry subkey:


    Note: The worm monitors the above registry entry and recreates it if it is deleted.

  8. Adds the values:

    "5f54e750-ce26-11cf-8e43-00a0c911005a" = "mnlnnimimnoiuilnvjkinnkitjwjnimntntm"
    "F4FC596D-DFFE-11CF-9551-00AA00A3DC45" = "mbmabptebkjcdlgtjmskjwtsdhjbmkmwtrak"
    "190B7910-992A-11cf-8AFA-00AA00C00905" = "gclclcejjcmjdcccoikjlcecoioijjcjnhng"
    "72E67120-5959-11cf-91F6-C2863C385E30" = "ibcbbbebqbdbciebmcobmbhifcmciibblgmf"
    "096EFC40-6ABF-11cf-850C-08002B30345D" = "knsgigmnmngnmnigthmgpninrmumhgkgrlrk"
    "556C75F1-EFBC-11CF-B9F3-00A0247033C4" = "xybiedobrqsprbijaegcbislrsiucfjdhisl"
    "4D553650-6ABE-11cf-8ADB-00AA00C00905" = "gfjmrfkfifkmkfffrlmmgmhmnlulkmfmqkqj"
    "57CBF9E0-6AA7-11cf-8ADB-00AA00C00905" = "aahakhchghkhfhaamghhbhbhkbpgfhahlfle"
    "9E799BF1-8817-11cf-958F-0020AFC28C3B" = "uqpqnqkjujkjjjjqwktjrjkjtkupsjnjtoun"
    "78E1BDD1-9941-11cf-9756-00AA00C00908" = "yjrjvqkjlqqjnqkjvprqsjnjvkuknjpjtoun"
    "DC4D7920-6AC8-11cf-8ADB-00AA00C00905" = "iokouhloohrojhhhtnooiokomiwnmohosmsl"
    "7C35CA30-D112-11cf-8E72-00A0C90F26F8" = "whmhmhohmhiorhkouimhihihwiwinhlosmsl"
    "2c49f800-c2dd-11cf-9ad6-0080c7e7b78d" = "mlrljgrlhltlngjlthrligklpkrhllglqlrk"
    "899B3E80-6AC6-11cf-8ADB-00AA00C00905" = "wjsjjjlqmjpjrjjjvpqqkqmqukypoqjquoun"
    "B1EFCCF0-6AC1-11cf-8ADB-00AA00C00905" = "qqkjvqpqmqjjpqjjvpqqkqmqvkypoqjquoun"
    "6FB38640-6AC7-11cf-8ADB-00AA00C00905" = "gdjkokgdldikhdddpjkkekgknesjikdkoioh"
    "E32E2733-1BC5-11d0-B8C3-00A0C90DCA10" = "kmhfimlflmmfpffmsgfmhmimngtghmoflhsg"
    "4250E830-6AC2-11cf-8ADB-00AA00C00905" = "kjljvjjjoquqmjjjvpqqkqmqykypoqjquoun"
    "BC96F860-9928-11cf-8AFA-00AA00C00905" = "mmimfflflmqmlfffrlnmofhfkgrlmmfmqkqj"

    to the registry subkey:


    which enables the %System%\MSWINSCK.OCX file to function.

  9. May modify values in the following registry subkeys:

    HKEY_CURRENT_USER\Control Panel\BMale

  10. Disables the mouse and keyboard functionality the first time the worm is executed on the compromised computer.

  11. Displays the following icon in the Windows Task Bar when it detects the presence of antivirus software:

    Note: The text "Update Please wait" is displayed when a user hovers over the icon.

  12. Monitors the titles of active windows. If the user is browsing with Windows Explorer, the window title is the path to the current folder. The worm uses this information to search the current folder for the file desktop.ini. If this file exists the worm copies itself to the current folder as WinZip_Tmp.exe and creates the file temp.htt.

  13. Deletes the following files:

    • %ProgramFiles%\DAP\*.dll
    • %ProgramFiles%\BearShare\*.dll
    • %ProgramFiles%\Symantec\LiveUpdate\*.*
    • %ProgramFiles%\Symantec\Common Files\Symantec Shared\*.*
    • %ProgramFiles%\Norton AntiVirus\*.exe
    • %ProgramFiles%\Alwil Software\Avast4\*.exe
    • %ProgramFiles%\\VSO\*.exe
    • %ProgramFiles%\\Agent\*.*
    • %ProgramFiles%\\shared\*.*
    • %ProgramFiles%\Trend Micro\PC-cillin 2002\*.exe
    • %ProgramFiles%\Trend Micro\PC-cillin 2003\*.exe
    • %ProgramFiles%\Trend Micro\Internet Security\*.exe
    • %ProgramFiles%\NavNT\*.exe
    • %ProgramFiles%\Morpheus\*.dll
    • %ProgramFiles%\Kaspersky Lab\Kaspersky Anti-Virus Personal\*.ppl
    • %ProgramFiles%\Kaspersky Lab\Kaspersky Anti-Virus Personal\*.exe
    • %ProgramFiles%\Grisoft\AVG7\*.dll
    • %ProgramFiles%\TREND MICRO\OfficeScan\*.dll
    • %ProgramFiles%\Trend Micro\OfficeScan Client\*.exe
    • %ProgramFiles%\LimeWire\LimeWire 4.2.6\LimeWire.jar

      Note: %ProgramFiles% is a variable that refers to the program files folder. By default, this is C:\Program Files.

  14. Queries the following values:

    "Home Directory"

    under the following registry subkeys:

    Uninstall\Panda Antivirus 6.0 Platinum

    and deletes all .exe files found in the folders it locates.

  15. Queries the value:


    in the following registry subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\KasperskyLab\InstalledProducts\Kaspersky Anti-Virus Personal

    and deletes all files found in the folder it locates.

  16. Queries the value:


    in the following registry subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\Iface.exe

    and deletes all *.exe and *.ppl files in the folder it locates.

  17. Closes windows whose title contains any of the following strings:

    • SCAN
    • VIRUS
    • MCAFEE
    • NORTON
    • FIX

  18. Deletes the values:


    from the following registry subkeys:


  19. Gathers email addresses from files with the following extensions:


    The worm also gathers email addresses from files with one of the following strings in the full name :

    • CONTENT.

  20. Attempts to send itself as an email to the addresses it gathers using its own SMTP engine. The email will have the following characteristics:

    One of the following:

    • *Hot Movie*
    • A Great Video
    • Fw:
    • Fw: DSC-00465.jpg
    • Fw: Funny :)
    • Fw: Picturs
    • Fw: Real show
    • Fw: SeX.mpg
    • Fw: Sexy
    • Fwd: Crazy illegal Sex!
    • Fwd: image.jpg
    • Fwd: Photo
    • give me a kiss
    • Miss Lebanon 2006
    • My photos
    • Part 1 of 6 Video clipe
    • Photos
    • Re:
    • School girl fantasies gone bad

      Message body:
      One of the following:

    • Note: forwarded message attached. You Must View This Videoclip!
    • >> forwarded message
    • Re: Sex Video
    • i just any one see my photos.
    • It's Free :)
    • The Best Videoclip Ever
    • Hot XXX Yahoo Groups
    • Fuckin Kama Sutra pics
    • ready to be FUCKED ;)
    • forwarded message attached.
    • VIDEOS! FREE! (US$ 0,00)
    • What?
    • i send the file.
    • Helloi attached the details.
    • Thank you
    • the file i send the details
    • hello,
    • Please see the file.
    • how are you?
    • i send the details.

      One of the following:

    • 007.pif
    • 392315089702606E-02,.scR
    • 677.pif
    • Adults_9,zip.sCR
    • Arab sex DSC-00465.jpg
    • Attachments[001],B64.sCr
    • Clipe,zip.sCr
    • document.pif
    • DSC-00465.Pif
    • DSC-00465.pIf
    • eBook.pdf
    • eBook.PIF
    • image04.pif
    • New Video,zip
    • New_Document_file.pif
    • photo.pif
    • Photos,zip.sCR
    • School.pif
    • SeX,zip.scR
    • Sex.mim
    • Video_part.mim
    • WinZip,zip.scR
    • WinZip.BHX
    • Word
    • 04.pif
    • DSC-00465.Pif
    • DSC-00465.pIf
    • image04.pif

      The attachment may be an executable file or a MIME file that contains an executable file. Those attachments that are MIME files may have the following file names:

    • 3.92315089702606E02.UUE
    • Attachments[001].B64
    • Attachments00.HQX
    • Attachments001.BHX
    • eBook.Uu
    • Original Message.B64
    • Sex.mim
    • SeX.mim
    • Video_part.mim
    • WinZip.BHX
    • Word_Document.hqx
    • Word_Document.uu

      These files may also have one the following file names:

    • 392315089702606E-02
    • Clipe
    • Miss
    • Photos
    • Sweet_09

      These file names will be combined with one of the following extensions:

    • .b64
    • .BHx
    • .HQX
    • .mim
    • .uu
    • .UUE
    • .XxE

      If the attachment is a MIME file, it may contain a file with one of the following file names:

    • 392315089702606E-02,UUE[BLANK SPACES].scr
    • Adults_9,zip[BLANK SPACES].scr
    •[BLANK SPACES].scr
    • Atta[001],zip[BLANK SPACES].scr
    • Attachments,zip[BLANK SPACES].scr
    • Attachments[001],B64[BLANK SPACES].scr
    • Clipe,zip[BLANK SPACES].scr
    • New Video,zip[BLANK SPACES].scr
    • Photos,zip[BLANK SPACES].scr
    • SeX,zip[BLANK SPACES].scr
    • WinZip,zip[BLANK SPACES].scr
    •[BLANK SPACES].scr
    • Word[BLANK SPACES].scr
    •[BLANK SPACES].scr

      The attachment may use the following icon:

  21. Searches the network for the following shared folders, where it copies itself as WINZIP_TMP.EXE:

    • ADMIN$
    • C$

      Note: The worm also copies itself using the same file name to network shares protected by weak passwords.

  22. Copies itself to network shares as the following:

    C$\Documents and Settings\All Users\Start Menu\Programs\Startup\WinZip Quick Pick.exe

  23. Deletes the following file from network shares:

    C$\Documents and Settings\All Users\Start Menu\Programs\Startup\WinZip Quick Pick.lnk

  24. Attempts to access the following URL:


  25. Enumerates the computers in the same domain as the host computer by using WNetOpenEnum.

  26. Executes the command "net use \\[COMPUTER NAME] /user:administrator" to connect to that computer.

    • If the user on the compromised computer is already connected to some other network computer, the worm will be able to use that connection.
    • [COMPUTER NAME] is a remote computer name and "" is a blank password.

  27. Attempts to delete the following folders on the computer it connects to:

    • \C$\Program Files\Norton AntiVirus
    • \C$\Program Files\Common Files\symantec shared
    • \C$\Program Files\Symantec\LiveUpdate
    • \C$\Program Files\\VSO
    • \C$\Program Files\\Agent
    • \C$\Program Files\\shared
    • \C$\Program Files\Trend Micro\PC-cillin 2002
    • \C$\Program Files\Trend Micro\PC-cillin 2003
    • \C$\Program Files\Trend Micro\Internet Security
    • \C$\Program Files\NavNT
    • \C$\Program Files\Panda Software\Panda Antivirus Platinum
    • \C$\Program Files\Kaspersky Lab\Kaspersky Anti-Virus Personal
    • \C$\Program Files\Kaspersky Lab\Kaspersky Anti-Virus Personal Pro
    • \C$\Program Files\Panda Software\Panda Antivirus 6.0
    • \C$\Program Files\CA\eTrust EZ Armor\eTrust EZ Antivirus

  28. Attempts to execute the following command on the compromised computer to execute its copy at the end of the hour:

    at [COMPUTER NAME] [HOUR]:59 /interactive \\[COMPUTER NAME]\Admin$\WINZIP_TMP.exe
    at [COMPUTER NAME] [HOUR]:59 /interactive \\[COMPUTER NAME]\C$\WINZIP_TMP.exe

    Note: [COMPUTER NAME] is a remote computer name and [HOUR] represents the hour when propagation begins.

  29. 30 minutes after the worm file UPDATE.EXE is loaded into memory (which could be when a compromised computer is started up or when the worm is executed on a computer), the worm checks if the date is the 3rd of the month. If it is the 3rd of the month the worm will attempt to overwrite files with the following extensions in available drives from A to Z:

    • *.doc
    • *.xls
    • *.mdb
    • *.mde
    • *.ppt
    • *.pps
    • *.zip
    • *.rar
    • *.pdf
    • *.psd
    • *.dmp

    • The worm will not overwrite files in the first available drive. For example if the first available drive is the C drive, the worm will overwrite files in available drives from D to Z.
    • The files are overwritten with the following text:

      DATA Error [47 0F 94 93 F4 F5]


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.


Removal using the W32.Blackmal@mm Removal Tool
Symantec Security Response has developed a removal tool to clean the infections of W32.Blackmal.E@mm. Use this removal tool first, as it is the easiest way to remove this threat.

Note: The threat targets AV products, so if any of the targeted files have been deleted, then the AV product may need to be reinstalled after using the removal tool.

Manual Removal:

The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

  1. Disable System Restore (Windows Me/XP).
  2. Update the virus definitions.
  3. Run a full system scan and delete all the files detected.
  4. Delete any values added to the registry.
For specific details on each of these steps, read the following instructions.

1. To disable System Restore (Windows Me/XP)
If you are running Windows Me or Windows XP, we recommend that you temporarily turn off System Restore. Windows Me/XP uses this feature, which is enabled by default, to restore the files on your computer in case they become damaged. If a virus, worm, or Trojan infects a computer, System Restore may back up the virus, worm, or Trojan on the computer.

Windows prevents outside programs, including antivirus programs, from modifying System Restore. Therefore, antivirus programs or tools cannot remove threats in the System Restore folder. As a result, System Restore has the potential of restoring an infected file on your computer, even after you have cleaned the infected files from all the other locations.

Also, a virus scan may detect a threat in the System Restore folder even though you have removed the threat.

For instructions on how to turn off System Restore, read your Windows documentation, or one of the following articles:
When you are completely finished with the removal procedure and are satisfied that the threat has been removed, reenable System Restore by following the instructions in the aforementioned documents.

For additional information, and an alternative to disabling Windows Me System Restore, see the Microsoft Knowledge Base article: Antivirus Tools Cannot Clean Infected Files in the _Restore Folder (Article ID: Q263455).

2. To update the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:
  • Running LiveUpdate, which is the easiest way to obtain virus definitions:
    • If you use Norton AntiVirus 2006, Symantec AntiVirus Corporate Edition 10.0, or newer products, LiveUpdate definitions are updated daily. These products include newer technology.
    • If you use Norton AntiVirus 2005, Symantec AntiVirus Corporate Edition 9.0, or earlier products, LiveUpdate definitions are updated weekly. The exception is major outbreaks, when definitions are updated more often.
  • Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted daily. You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to Virus Definitions (Intelligent Updater).

    The latest Intelligent Updater virus definitions can be obtained here: Intelligent Updater virus definitions. For detailed instructions read the document: How to update virus definition files using the Intelligent Updater.

3. To scan for and delete the infected files
  1. Start your Symantec antivirus program and make sure that it is configured to scan all the files.
  2. Run a full system scan.
  3. If any files are detected, click Delete.

Important: If you are unable to start your Symantec antivirus product or the product reports that it cannot delete a detected file, you may need to stop the risk from running in order to remove it. To do this, run the scan in Safe mode. For instructions, read the document, How to start the computer in Safe Mode . Once you have restarted in Safe mode, run the scan again.

After the files are deleted, restart the computer in Normal mode and proceed with the next section.

Warning messages may be displayed when the computer is restarted, since the threat may not be fully removed at this point. You can ignore these messages and click OK. These messages will not appear when the computer is restarted after the removal instructions have been fully completed. The messages displayed may be similar to the following:

Title: [FILE PATH]
Message body: Windows cannot find [FILE NAME]. Make sure you typed the name correctly, and then try again. To search for a file, click the Start button, and then click Search.

4. To delete the value from the registry
Important: Symantec strongly recommends that you back up the registry before making any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified subkeys only. For instructions refer to the document: How to make a backup of the Windows registry.
  1. Click Start > Run.
  2. Type regedit
  3. Click OK.

    Note: If the registry editor fails to open the threat may have modified the registry to prevent access to the registry editor. Security Response has developed a tool to resolve this problem. Download and run this tool, and then continue with the removal.

  4. Navigate to the subkey:


  5. In the right pane, delete the value:

    "ScanRegistry" = "scanregw.exe /scan"

  6. Navigate to the subkey:


  7. In the right pane, reset the values to the original values, if applicable:

    "WebView" = "0"
    "ShowSuperHidden" = "0"

  8. Navigate to the subkey:


  9. In the right pane, reset the value to the original value, if applicable:

    "FullPath" = "0"

  10. Exit the Registry Editor.

Writeup By: Rodney Andres