Analysis by: Miguel Carlo Ang
ALIASES:

TrojanDownloader:JS/Nemucod.K(Microsoft);JS/TrojanDownloader.Nemucod.AF trojan(NOD32);JS/Nemucod.AF!tr(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

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: 14,451 bytes
File Type: JS
Memory Resident: Yes
Initial Samples Received Date: 21 Mar 2015

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.

Installation

This Trojan drops and executes the following files:

  • %User Temp%\{8 random}.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.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • {BLOCKED}andsummermoon.com/document.php?rnd={data}&{data}={data}
  • {BLOCKED}esternplows.com/document.php?rnd={data}&{data}={data}
  • {BLOCKED}rmsystems.com/document.php?rnd={data}&{data}={data}