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JAVA_LOOBNUR.B

April 03, 2014
 Analysis by: Jaime Benigno Reyes
 ALIASES:

Mal/JavaGen-D (Sophos) ,Trojan horse Java/Agent.KU (AVG) ,Trojan.Java.Agent, Trojan.Java.Agent (Ikarus) ,Worm.Java.AutoRun.j (Kaspersky) ,Worm:Java/Runatox.B (Microsoft) ,[a.class]:Generic.dx!bbmd (McAfee) ,Java/Autorun.A worm, Java/Autorun.A worm (Eset) ,Trojan.Maljava (Symantec) ,Trojan.Java.Cilo.a (v) (Sunbelt)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW


This worm arrives via removable drives. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It opens random ports.

  TECHNICAL DETAILS

File Size:

Varies

File Type:

JAR

Memory Resident:

Yes

Initial Samples Received Date:

02 Apr 2014

Arrival Details

This worm arrives via removable drives.

It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This worm drops the following files:

  • %User Temp%\hsperfdata_{username}\{random filename}.{random file extension} - detected as TROJ_BEYOND.B
  • %User Temp%\hsperfdata_{username}\{random number}

It drops and executes the following files:

  • %User Temp%\jar_cache{random number}.tmp - also detected as JAVA_LOOBNUR.B

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

It drops the following non-malicious files:

  • %User Temp%\hsperfdata_{username}\{system filename}.exe - Normal Java File

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

It creates the following folders:

  • %User Temp%\hsperfdata_{username}

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

Other System Modifications

This worm adds the following registry entries as part of its installation routine:

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\Active Setup\Installed Components\
{CLSID}
StubPath = ""cMd.ExE /Q /c START "" /i /b JAvAw.exE -classpath "%User Temp%\jar_cache{random number}" a"

Propagation

This worm drops the following copy(ies) of itself in all removable drives:

  • {removable drive letter}:\RECYCLER\{SID}\{random filename}.{random file extension}

Backdoor Routine

This worm opens a random port to allow a remote user to connect to the affected system. Once a successful connection is established, the remote user executes commands on the affected system.

Other Details

This worm connects to the following URL(s) to check for an Internet connection:

  • thepiratebay.org
  • msn.com
  • bing.com
  • alibaba.com
  • paypal.com
  • photobucket.com
  • imageshack.us
  • youporn.com
  • go.com
  • xhamster.com
  • blogspot.com
  • hotfile.com
  • facebook.com
  • live.com
  • megaupload.com
  • doubleclick.com
  • apple.com
  • google.com
  • livejasmin.com
  • adobe.com
  • megavideo.com
  • myspace.com
  • mediafire.com
  • bbc.co.uk
  • amazon.com
  • godaddy.com
  • yieldmanager.com
  • nytimes.com
  • 4shared.com
  • wordpress.com
  • linkedin.com
  • cnet.com
  • conduit.com
  • rapidshare.com
  • about.com
  • orkut.com
  • microsoft.com
  • craigslist.org
  • flickr.com
  • livejournal.com
  • pornhub.com
  • mozilla.com
  • tube8.com
  • wikipedia.org
  • twitter.com
  • aol.com
  • cnn.com
  • tumblr.com
  • ebay.com
  • yahoo.com
  • youtube.com
  • ask.com
  • xvideos.com
  • imdb.com

  SOLUTION

Minimum Scan Engine:

9.700

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Remove the malware/grayware file dropped/downloaded by JAVA_LOOBNUR.B

Step 3

Restart in Safe Mode

[ Learn More ]

Step 4

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

 
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Active Setup\Installed Components\{CLSID}
    • StubPath = ""cMd.ExE /Q /c START "" /i /b JAvAw.exE -classpath "%User Temp%\jar_cache{random number}" a"

Step 5

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Temp%\hsperfdata_{username}

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as JAVA_LOOBNUR.B. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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