Analysis by: rolandde
 Modified by: Karl Dominguez
 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 Trojan takes advantage of certain software vulnerabilities to download possibly malicious files.

This Trojan downloads a possibly malicious file from a certain URL. The URL where this malware downloads the said file depends on the parameter passed on to it by its components.

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

  TECHNICAL DETAILS

File Size: 4,992 bytes
File Type: Java Class
Initial Samples Received Date: 01 Nov 2011
Payload: Downloads files

Arrival Details

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

Download Routine

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

NOTES:

This Trojan downloads a possibly malicious file from a certain URL. The URL where this malware downloads the said file depends on the parameter passed on to it by its components.

It determines the type of the downloaded file, whether .EXE or .DLL, and saved it as follows:

  • %User Temp%\{Random number}.exe
  • %User Temp%\{Random number}.dll

It then executes the downloaded file.

  SOLUTION

Minimum Scan Engine: 9.200
FIRST VSAPI PATTERN FILE: 8.540.04
FIRST VSAPI PATTERN DATE: 01 Nov 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

Search and delete these files

[ 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%\{Random number}.exe
  • %User Temp%\{Random number}.dll

Step 3

Scan your computer with your Trend Micro product to delete files detected as JAVA_BLACOLE.ERC. 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.

Step 4

Download and apply this security patch Refrain from using these products until the appropriate patches have been installed. Trend Micro advises users to download critical patches upon release by vendors.


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