JS_LOCKY.DLDVK

July 18, 2016
 Analysis by: Michael Jay Villanueva
 ALIASES:

JS/Locky.AN (F-Protect); Trojan.JS.Downloader.DPT (BitDefender); JS/Nemucod.3FD6!tr.dldr (Fortinet)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Spammed via email, Downloaded from the Internet

This Trojan arrives as attachment to mass-mailed email messages. 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 executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

  TECHNICAL DETAILS

File Size:

63,369 bytes

File Type:

JS

Initial Samples Received Date:

15 Jul 2016

Payload:

Connects to URLs/IPs, Downloads files

Arrival Details

This Trojan arrives as attachment to mass-mailed email messages.

It 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 saves the files it downloads using the following names:

  • %User Temp%\EjZnwMgAAYZdU
  • %User Temp%\EjZnwMgAAYZdU.exe

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

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 connects to the following possibly malicious URL:

  • http://{BLOCKED}roxy.com/d5bdps4i
  • http://{BLOCKED}i.net/ubfavow

  SOLUTION

Minimum Scan Engine:

9.800

FIRST VSAPI PATTERN FILE:

12.652.06

FIRST VSAPI PATTERN DATE:

14 Jul 2016

VSAPI OPR PATTERN File:

12.653.00

VSAPI OPR PATTERN Date:

15 Jul 2016

NOTES:

Trend customers:

    Keep your pattern and scan engine files updated. Trend Micro antivirus software can clean or remove most types of computer threats. Malware, though, such as Trojans, scripts, overwriting viruses and joke programs which are identified as uncleanable, should simply be deleted.

All Internet users:

  • Use HouseCall - the Trend Micro online threat scanner to check for malware that may already be on your PC.
  • Catch malware/grayware before they affect your PC or network. Secure your Web world with Trend Micro products that offer the best anti-threat and content security solutions for home users, corporate users, and ISPs. Go here for more information on Trend Micro products that fit your needs.


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