W32.Badtrans.B@mm
Due to the increased rate of submissions, Symantec Security Response has upgraded the threat level of this worm from level 3 to level 4 as of November 26, 2001. W32.Badtrans.B@mm is a MAPI worm that emails itself out using different file names. It also creates the file \Windows\System\Kdll.dll. It uses functions from this file to log keystrokes. Infection Length: 29,020 bytes Virus Definitions: November 24, 2001
Wild:
Damage:
Distribution:
Technical description:This worm arrives as an
email with one of several attachment names and a
combination of two appended extensions. It contains a
set of bits that control its behavior:
These texts form the start of the words LOGon, PASsword, REMote, CONnection, TERminal, NETwork. There are also Russian versions of these same words in the list. If any of these words are found, then the key logging is enabled for 60 seconds. Every 30 seconds, the log file and the cached passwords are sent to one of these addresses or some others which are currently not operational:
If RAS support is present on the computer, then the worm will wait for an active RAS connection. When one is made, with a 33% chance, the worm will search for email addresses in *.ht* and *.asp in %Personal% and Internet Explorer %Cache%. If it finds addresses in these files, then it will send mail to those addresses using the victim's SMTP server. If this server is unavailable the worm will choose from a list of its own. The attachment name will be one of the following:
In all cases, the worm will append two extensions. The first will be one of the following:
The second extension that is appended to the file name is one of the following:
The resulting file name would look
similar to CARD.Doc.pif or NEWS_DOC.mp3.scr.
Email
messages use the malformed MIME exploit to allow the
attachment to execute in Microsoft Outlook without
prompting. For information on this, go to:
The worm writes email addresses to the %System%\Protocol.dll file to prevent multiple emails to the same person. Additionally, the sender's email address will have the "_" character prepended to it, to prevent replying to infected mails to warn the sender (eg user@website.com becomes _user@website.com). After sending mail,
the worm adds the value to the registry
key Removal instructions:To remove this worm, follow the instructions for your operating system. Basic instructionsWindows 95/98/Me
2. Run Norton AntiVirus and delete all files that are detected as W32.Badtrans.B@mm. 3. Remove the value that it added to the registry.
2. Run Norton AntiVirus and delete all files that are detected as W32.Badtrans.B@mm. 3. Remove the value that it added to the registry. To remove files
that cannot be deleted by NAV:
2. Run the scan again, and delete any files detected as W32.Badtrans.B@mm. 3. When the scan is finished, go on to the section To edit the registry.
To edit the registry: CAUTION: We strongly recommend that you back up the system registry before you make any changes. Incorrect changes to the registry could result in permanent data loss or corrupted files. Please make sure that you modify only the keys that are specified. Please see the document How to back up the Windows registry before you proceed. This document is available from the Symantec Fax-on-Demand system. In the U.S. and Canada, call (541) 984-2490, select option 2, and then request document 927002.
2. Type regedit and then click OK. The Registry Editor opens. 3. Navigate to the following key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce 4. In the right pane, delete the following value: Kernel32 kernel32.exe 5. Click Registry, and then click Exit. Additional information:Prevention
Write-up by: Peter Ferrie
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C l e a rKako ukloniti ovaj trojanac:Fajl koji Vam je na raspolaganju na CLR-BAD.bat (desni Click/ Save Target As...) preuzmite i iskopirajte na disketu A:\ (ili C:\), potom restartujte operativni System u DOS-u (Restart in MS-DOS mode). U promptu otkucajte: a:\CLR-BAD.bat (ili c:\CLR-BAD.bat), pa pritisnite Enter, a kada se proces završi EXIT<Enter> za povratak u OS Windows. U nastavku je dat prikaz izvršnih linija u ovom fajlu: echo UKLANJA tragove Trojanca W32.Badtrans.B@mm | |||||||||||||||
