JAVA_DLOAD.ZZC

December 23, 2011
 Analysis by: Erika Bianca Mendoza
 Modified by: Kathleen Notario
 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW


This malware exploits a known vulnerability in Java to drop malicious files. Routine of the dropped files are then exhibited on the affected system.

To get a one-glance comprehensive view of the behavior of this Trojan, refer to the Threat Diagram shown below.

This Trojan may be hosted on a website and run when a user accesses the said website.

It executes the files it drops, prompting the affected system to exhibit the malicious routines they contain.

  TECHNICAL DETAILS

File Size:

1,377 bytes

File Type:

Java Class

Initial Samples Received Date:

10 Dec 2011

Arrival Details

This Trojan may be hosted on a website and run when a user accesses the said website.

Installation

This Trojan drops the following files:

  • %User Temp%\~spawn{random numbers}.tmp.dir\ATxBtCuy.exe - detected by Trend Micro as TROJ_PPOINTER.SM
  • %User Temp%\~spawn{random numbers2}.tmp.dir\ATxBtCuy.exe - detected by Trend Micro as TROJ_PPOINTER.SM

(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.)

It creates the following folders:

  • %User Temp%\~spawn{random numbers}.tmp.dir
  • %User Temp%\~spawn{random numbers2}.tmp.dir

(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.)

Dropping Routine

This Trojan executes the files it drops, prompting the affected system to exhibit the malicious routines they contain.

Other Details

More information on this vulnerability can be found below:

NOTES:

It exploits the following vulnerability in Java:

  • Unspecified Vulnerability in the Java Runtime Environment

This Java applet contains metasploit.DAT, which identifies the name of the file and the number of times that it is dropped into the system.

Sample content of metasploit.DAT is as follows:

Spawn=2 Executable=ATxBtCuy.exe

The executable file ATxBtCuy.EXE is included in the .JAR file.

  SOLUTION

Minimum Scan Engine:

9.200

FIRST VSAPI PATTERN FILE:

8.634.07

FIRST VSAPI PATTERN DATE:

10 Dec 2011

VSAPI OPR PATTERN File:

8.635.00

VSAPI OPR PATTERN Date:

10 Dec 2011

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Remove malware/grayware files dropped/downloaded by JAVA_DLOAD.ZZC

Step 3

Close all opened browser windows

Step 4

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%\~spawn{random numbers}.tmp.dir
  • %User Temp%\~spawn{random numbers2}.tmp.dir

Step 5

Scan your computer with your Trend Micro product to delete files detected as JAVA_DLOAD.ZZC. 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.

NOTES:
For updates on available workarounds and patches for this vulnerability, please refer to the following page:

  • http://www.oracle.com/technetwork/topics/security/javacpuoct2011-443431.html


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