Analysis by: Kathleen Notario
 Modified by: Christopher Daniel So
ALIASES:

TrojanDownloader:Java/OpenConnection.GS (Microsoft), Exploit:Java/CVE-2010-0094.AC (Microsoft), Trojan.Maljava (Symantec), Trojan-Downloader.Java.OpenConnection.aw (Kaspersky), Mal/JavaImr-D (Sophos), Mal/JavaEsa-A (Sophos)

 PLATFORM:

Windows 2000, XP, Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

This Trojan executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

It requires its main component to successfully perform its intended routine.

  TECHNICAL DETAILS

File Size: Varies
File Type: Java Class
Memory Resident: No
Initial Samples Received Date: 10 Nov 2010
Payload: Downloads files

Download Routine

This Trojan takes advantage of the following software vulnerabilities to download possibly malicious files:

  • CVE-2010-0094

It saves the files it downloads using the following names:

  • %User Temp%\mstsc.exe

(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 then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

Other Details

This Trojan requires its main component to successfully perform its intended routine.

NOTES:

For more information on the aforementioned vulnerabilities, please see the following pages:

  SOLUTION

Minimum Scan Engine: 8.900
VSAPI PATTERN File: 7.610.07
VSAPI PATTERN Date: 11 Nov 2010
VSAPI PATTERN Date: 11/11/2010 12:00:00 AM

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

Close all opened browser windows

Step 3

Search and delete this file

[ Learn More ]
There may be some component files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden files and folders in the search result. %User Temp%\mstsc.exe

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_JAVA.BR. 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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