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  3. Trojan.Jnanabot

Trojan.Jnanabot

Risk Level 1: Very Low

Discovered:
October 25, 2010
Updated:
October 26, 2010 4:42:46 PM
Type:
Trojan
Infection Length:
171,980 bytes
Systems Affected:
Mac OS X, Windows 2000, Windows 7, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows Server 2008, Windows Vista, Windows XP
When the Trojan is executed, it creates the following files:
  • %UserProfile%\.jnana\jnana.tsa
  • %UserProfile%\.jnana\siv.exe
  • %UserProfile%\.jnana\VFxdSys.exe
  • %UserProfile%\.jnana\VfxdSysAdm.exe
  • %UserProfile%\.jnana\ofex.exe
  • %UserProfile%\.jnana\cas.scp


Next, the Trojan creates the following registry entry so that it executes whenever Windows starts:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run\"msjavadll" = "javaw-jar\ %UserProfile%"\.jnana\jnana.tsa"

It also creates one of the following registry entries, depending on the OS version. If the version is Windows Vista, Windows 2008, or Windows 7, the Trojan creates the following registry entry:
HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows\Run\"VFXDSys Compatibility Synchronisation" = "%UserProfile%\vfxdsys.exe"

If the OS version is not one of the above three, it creates the following registry entry:
HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows\Run\"VFXDSys Compatibility Synchronisation" = "%UserProfile%\Application Data\Microsoft\VfxdSys Drivers\vfxdsys.exe"

Next, the Trojan may download files from the following locations:
  • [http://]motherhost.sytes.net/ofex[REMOVED]
  • [http://]motherhost.sytes.net/VfxdS[REMOVED]
  • www.nirsoft.ne/utils/nircmd.zip


The above .zip files may contain the following files:
  • %CurrentFolder%\siv.exe
  • %CurrentFolder%\VFxdSys.exe
  • %CurrentFolder%\VfxdSysAdm.exe


The Trojan may then attempt to download the following configuration file, which contains updates to itself:
jnana.tsa

It may download the above file from the following location:
http://[DOMAIN NAME]/jnana.tsa

Note: Where [DOMAIN NAME] is chosen from a list of predetermined domains.

The Trojan stops the following Windows security service:
wscsvc

Next, the Trojan may connect to the following locations:
  • astroboy.zapto.org
  • bora.servepics.com
  • brando.serveblog.net
  • bruton.servehalflife.com
  • download.microsoft.com
  • epsilon.servequake.com
  • gerhardt.sytes.net
  • hercules.serveirc.com
  • jasperhsv.000page.com
  • loggerme.001webs.com
  • logmeto.serveblog.net
  • mont-blanc.myftp.org
  • motherhost.sytes.net
  • motherhost.sytes.net
  • north2.bounceme.net
  • pluto.serveblog.net
  • sb-pq2vki2k.no-ip.org
  • videoslogger.000page.com
  • www.facebook.com
  • www.nirsoft.net
  • www.whatismyip.com

The threat may download a file named applet_hosts.txt from the following domains:
  • north2.bounce
  • bruton2010:afc2pug
  • mont-blanc.com
  • brando.serveblog.net
  • gerhardt.sytes.net
  • bruton.servehalflife.com
  • bora.servepics.com
  • pluto.serveblog.net
  • epsilon.servequake.com
  • astroboy.zapto.org
  • synchost.no-ip.org
  • .no-ip.org
  • servepics.com
  • sytes.net
  • zapto.org
  • strangled.net
  • mooo.com
  • chickenkiller.com
  • informatix.com
  • casablanca.net.ru
  • orange.org.ru
  • lemon.org.ru
  • melon.org.ru
  • apple.org.ru
  • myfruit.org.ru
  • good.one.pl
  • toutges.us
  • uk.to
  • qc.to
  • lamer.la
  • r00t.la
  • tang.la
  • shit.la
  • m3th.org
  • rocketcat.info
  • braintec.c
  • shell.la
  • us.to
  • computersforpeace.net
  • xbox2.bz
  • syndro
  • naken.net
  • zitaholdings.com
  • pisoft.ch
  • njhurst.org
  • njhurst.com
  • myrkraverk.net
  • wtf.la
  • asianfreshproduce.com
  • kaleebso.com
  • base-v.ch
  • rockingwranchinc.com
  • milstone.org
  • tallerideas.com
  • orientalecstasy.co
  • orientalxtasy.co
  • sexypenguins.com
  • sektori.org
  • milstone.net
  • tophi.net
  • tophi.org
  • xpresit.net
  • bocis-c59.com
  • biz.tm
  • verymad.net
  • digital-forever.co
  • rwbcode.com
  • leedichter.com
  • weissdecisions.com
  • soussa-csc.com
  • legalmusicsearc
  • lesbianbat
  • yzin.com
  • digitalshop.us
  • logout.us
  • orgoro.com
  • townoftiburon.org
  • igster.org
  • nakedracer.biz
  • lachgastuning.info
  • nitrousexpress.info
  • mooo.info
  • aintno.info
  • mehrps.info
  • yoogle.info
  • mafia-ag.info
  • iiiii.info
  • freezed.info
  • yovoodoo.info
  • tinyint.info
  • bigbox.info
  • drugdealer24.info
  • desperate.info
  • njmstudios.co
  • gna.biz
  • lau.biz
  • photo-frame.com
  • dis-cover.info
  • isff.com
  • rumbaypelo.co
  • slowblog.co
  • ricardo24.ch
  • urinechicks.com
  • plorp.com
  • bot.nu
  • alfalcons.com
  • soccon.net
  • professionalcopy.net
  • ftwnet.com
  • 1lookitupongoogle.com

The Trojan may record key strokes and send the stored information to a remote server.

If the user is logged into Facebook, the Trojan may post messages that contain malicious links on their profile and friends' pages.

The messages may appear as follows:
As you are on my friends list I thought I would let you know I have decided to end my life.
For reasons that will be clear please visit my video on this site.
Thanks for being my friend. :(
[http://]facebookvideos.zapto.org/showv[REMOVED]

The Trojan opens a back door that allows a remote attacker to perform the following actions on the compromised computer:
  • Perform SYN and UDP flood attacks
  • Download and execute files
  • Take screenshots
  • Send spam email

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: Jeet Morparia and Mario Ballano
Summary| Technical Details| Removal

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