JS_BLACOLE.BCX

 Analysis by: Mark Joseph Manahan

 ALIASES:

JS/Kryptik.YD trojan (Eset), Trojan.Malscript (Symantec), Exploit.JS.Blacole (Ikarus)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware


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.

As of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size:

30,192 bytes

File Type:

JS

Initial Samples Received Date:

21 Sep 2012

Payload:

Connects to URLs/IPs, 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 connects to the following website(s) to download and execute a malicious file:

  • http://{BLOCKED}fismo.net/detects/rates-event_convinced-sent.php?peleoe=0403340834&fvc=080b3504370635333802&xgs=04&cuicxe=qiez&awniy=iqjceb

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

  • CVE-2006-0003 (Unspecified vulnerability in the RDS.Dataspace ActiveX control, which is contained in ActiveX Data Objects (ADO) and distributed in Microsoft Data Access Components (MDAC) 2.7 and 2.8, allows remote attackers to execute arbitrary code via unknown attack vectors.)

It saves the files it downloads using the following names:

  • {current directory}\c5165c7.exe

As of this writing, the said sites are inaccessible.

  SOLUTION

Minimum Scan Engine:

9.200

FIRST VSAPI PATTERN FILE:

9.412.02

FIRST VSAPI PATTERN DATE:

21 Sep 2012

VSAPI OPR PATTERN File:

9.413.00

VSAPI OPR PATTERN Date:

22 Sep 2012

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 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.
  • {current directory}\c5165c7.exe

Step 3

Scan your computer with your Trend Micro product to delete files detected as JS_BLACOLE.BCX 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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