W32.Mugly.H@mm

SUMMARY

W32.Mugly.H@mm is a worm that uses its own SMTP engine to spread by sending itself as an email attachment to addresses gathered from the compromised computer. The email will have a variable subject line and a variable attachment name. The attachment will have an .scr file extension.

The worm also drops and runs a variant of W32.Spybot.Worm.

Behavior

Symptoms

Transmission

Protection

• Virus Definitions (LiveUpdate™ Weekly) February 2, 2005
• Virus Definitions (Intelligent Updater) January 31, 2005

Threat Assessment

Wild

• Wild Level: Low
• Number of Infections: 0 - 49
• Number of Sites: 0 - 2
• Geographical Distribution: Low
• Threat Containment: Easy
• Removal: Easy

Damage

• Damage Level: Medium
• Payload: Drops and executes a W32.Spybot.Worm variant.
• Large Scale E-mailing: Sends a copy of itself to all addresses found on the compromised computer.

Distribution

• Distribution Level: High
• Name of Attachment: Varies with .scr file extension.

TECHNICAL DETAILS

When W32.Mugly.H@mm is executed, it performs the following actions:

1. Copies itself as the following:
   
   
   • %System%xxz.tmp
   • %System%attached.zip
     
     Note: %System% is a variable that refers to the System folder. By default, this is C:WindowsSystem (Windows 95/98/Me), C:WinntSystem32 (Windows NT/2000), or C:WindowsSystem32 (Windows XP).
     
     
2. Drops and executes a W32.Spybot.Worm variant in the %System% folder using one of the following file names:
   
   
   • svchosts.exe
   • dllman.exe
   • winasp.exe
   • windasp.exe
   • winexec32.exe
     
     
3. Creates the following non-viral files:
   
   
   • %System%ANSMTP.DLL (an SMTP engine)
   • %System%szip.dll
   • %System%uglym.jpg
     
     
4. Opens a browser window to display the image file %System%uglym.jpg:
   
   
   
   
5. Gathers email addresses from files with the following extensions:
   
   
   • .adb
   • .asp
   • .dbx
   • .doc
   • .htm
   • .html
   • .php
   • .sht
   • .tbb
   • .txt
   • .wab
     
     The worm avoids email addresses that contain the following strings:
     
     
   • .gov
   • ada
   • avg
   • gri
   • icro
   • lavat
   • mcae
   • nod
   • panda
   • rsky
   • soph
   • sophos
   • symac
     
     
6. Registers its own SMTP engine by creating the following registry entries:
   
   HKEY_CLASSES_ROOTANSMTP.MassSender
   HKEY_CLASSES_ROOTANSMTP.MassSender.1
   HKEY_CLASSES_ROOTANSMTP.OBJ
   HKEY_CLASSES_ROOTANSMTP.OBJ.1
   HKEY_CLASSES_ROOTCLSID{253664FB-EDFC-4AC6-BD69-B322F466AEED}
   HKEY_CLASSES_ROOTCLSID{887A577B-406B-48FF-80CB-70752BFCD7B4}
   HKEY_CLASSES_ROOTInterface{1E98666F-6260-42C9-B846-32B20FDEFE7B}
   HKEY_CLASSES_ROOTInterface{68B8DCDB-EFA4-420A-BB8A-71B9892A2063}
   HKEY_CLASSES_ROOTInterface{A5F6C90C-ABE4-4C57-A421-8C5A202AA9F8}
   HKEY_CLASSES_ROOTInterface{B13281CF-8778-4C98-AE23-ABBA4637A33D}
   HKEY_CLASSES_ROOTTypeLib{DE6317F7-6EF0-45C2-88D1-8E09415817F1}
   
   
7. Adds the value:
   
   "upme" = "dllman.exe"
   
   to the registry subkeys:
   
   HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRun
   HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersion
   RunServices
   HKEY_CURRENT_USERSoftwareMicrosoftOLE
   
   so that it is executed every time Windows starts.
   
   
8. Uses its own SMTP engine (%System%ANSMTP.DLL) to send itself to email addresses gathered from the compromised computer. The email has the following characteristics:
   
   From:
   One of the following:
   
   
   • adead_poet@hotmail.com
   • alex_edwards2000@msn.com
   • apiffany@cnet.com
   • blowjob_lips666@romance.com
   • britany_slut56@sex.com
   • cutie_pie@ogrish.com
   • easy_lay666@lovenet.com
   • good_fuck12@yahoo.com
   • hunk_hogan78@hallmark.com
   • mucle_bound_hunk892@download.com
   • romeorichard@google.com
   • sexy_guy88@aol.com
   • sexy_lil_thing@no-ip.com
   • tit_fuck_909@gmail.com
   • tit_fuck_909@paltalk.com
     
     Subject:
     One of the following:
     
     
   • Hhahahah lol!!!!
   • Your Pic On A Website!!
   • You have an Admirer
   • Rate My Pic.......
     
     Message:
     One of the following:
     
     
   • i found this on my computer from ages ago
     download it and see if you can remember it
     lol i was lauging like mad when i saw it! :D
     email me back haha...
   • I was looking at a website and came across
     this pic they look just like you! infact im sure
     it is lol , did you send this pic into them ? or
     is it someonce else :S ? Ive Added the pic in
     a zip so download it and check & email me back!
   • Hi ive sent 5 emails now and nobody will rate
     my pic!! :( please download and tell me what you
     think out of 10 , dont worry if you dont like it
     just say i wont be offended p.s i was drunk when
     it was taken :P
   • Someone has asked us on there behalf to send
     you this email and tell you they think you are
     wonderfull!!! All the The mystery persons details
     you need are enclosed in the attachment :)
     please download and respond telling us if you
     would like to make further contact with this
     person.
     
     Regards Hallmark Admirer Mail Admin.
     
     
     Attachment: attached.zip
     
     The attachment is a zipped copy of the worm. It contains one of the following files:
     
     
   • Photo_01.jpg.scr
   • Pic_001.jpg.scr
   • Scan_04.jpg.scr
   • Sexy_09.jpg.scr
   • admire_001.jpg.scr
   • for_you.jpg.scr
   • is_this_you.jpg.scr
   • love_04.jpg.scr

Recommendations

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

• Turn off and remove unneeded services. By default, many operating systems install auxiliary services that are not critical, such as an FTP server, telnet, and a Web server. These services are avenues of attack. If they are removed, blended threats have less avenues of attack and you have fewer services to maintain through patch updates.
• If a blended 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 (for example, all Windows-based computers should have the current Service Pack installed.). Additionally, please apply any security updates that are mentioned in this writeup, in trusted Security Bulletins, or on vendor Web sites.
• 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.
• Configure your email server to block or remove email that contains file attachments that are commonly used to spread viruses, such as .vbs, .bat, .exe, .pif and .scr files.
• Isolate infected computers quickly to prevent further compromising your organization. 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.

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. Restart the computer in Safe mode or VGA mode.
4. Run a full system scan and delete all the files detected as W32.Mugly.H@mm.
5. Reverse the changes made to the registry.
   

For 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:

• "How to disable or enable Windows Me System Restore"
• "How to turn off or turn on Windows XP System Restore"

Note: When you are completely finished with the removal procedure and are satisfied that the threat has been removed, re-enable 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: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
• 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 the Virus Definitions (Intelligent Updater).
  
  The Intelligent Updater virus definitions are available: Read "How to update virus definition files using the Intelligent Updater" for detailed instructions.

3. To restart the computer in Safe mode or VGA mode
Shut down the computer and turn off the power. Wait for at least 30 seconds, and then restart the computer in Safe mode or VGA mode.

• For Windows 95, 98, Me, 2000, or XP users, restart the computer in Safe mode. For instructions, read the document, "How to start the computer in Safe Mode."
• For Windows NT 4 users, restart the computer in VGA mode.
  
  

4. 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.
   • For Norton AntiVirus consumer products: Read the document, "How to configure Norton AntiVirus to scan all files."
   • For Symantec AntiVirus Enterprise products: Read the document, "How to verify that a Symantec Corporate antivirus product is set to scan all files."
2. Run a full system scan.
3. If any files are detected as infected with W32.Mugly.H@mm, click Delete.
4. Navigate to and delete the following files:
   
   • %System%attached.zip
   • %System%ANSMTP.DLL (an SMTP engine)
   • %System%szip.dll
   • %System%uglym.jpg
     

5. 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 keys only. Read the document, "How to make a backup of the Windows registry," for instructions.

1. Click Start > Run.
2. Type regedit
   
   Then click OK.
   
   
3. If you are not using ANSMTP, navigate to and delete the following registry entries:
   
   HKEY_CLASSES_ROOTANSMTP.MassSender
   HKEY_CLASSES_ROOTANSMTP.MassSender.1
   HKEY_CLASSES_ROOTANSMTP.OBJ
   HKEY_CLASSES_ROOTANSMTP.OBJ.1
   HKEY_CLASSES_ROOTCLSID{253664FB-EDFC-4AC6-BD69-B322F466AEED}
   HKEY_CLASSES_ROOTCLSID{887A577B-406B-48FF-80CB-70752BFCD7B4}
   HKEY_CLASSES_ROOTInterface{1E98666F-6260-42C9-B846-32B20FDEFE7B}
   HKEY_CLASSES_ROOTInterface{68B8DCDB-EFA4-420A-BB8A-71B9892A2063}
   HKEY_CLASSES_ROOTInterface{A5F6C90C-ABE4-4C57-A421-8C5A202AA9F8}
   HKEY_CLASSES_ROOTInterface{B13281CF-8778-4C98-AE23-ABBA4637A33D}
   HKEY_CLASSES_ROOTTypeLib{DE6317F7-6EF0-45C2-88D1-8E09415817F1}
   
   
4. Navigate to the following registry sub keys:
   
   HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRun
   HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersion
   RunServices
   HKEY_CURRENT_USERSoftwareMicrosoftOLE
   
   
5. In the right pane, delete the following:
   
   "upme" = "dllman.exe"
   
   
6. Exit the Registry Editor.
   
   
7. Restart the computer in Normal Mode.