JS_LOCKY.DLDSARJ


 ALIASES:

Troj/JsDldr-VM (Sophos), JS.Downloader.D (Symantec), TrojanDownloader:JS/Nemucod.AAS (Microsoft)

 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 as an attachment to email messages spammed by other malware/grayware or malicious users. 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 downloaded files whose malicious routines are exhibited by the affected system.

  TECHNICAL DETAILS

File Size:

17,617 bytes

File Type:

JS

Memory Resident:

No

Initial Samples Received Date:

09 Dec 2016

Arrival Details

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

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%\hEPxGnuLvlqeKJC
  • %User Temp%\hEPxGnuLvlqeKJC.zk

(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 executes downloaded files :

  • %User Temp%\hEPxGnuLvlqeKJC.zk

(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.)

whose malicious routines are exhibited by the affected system.

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}tta.com/b4tkcnc
  • http://{BLOCKED}n.co.kr/qs9mnktcm
  • http://{BLOCKED}i.cn/apievqkdo
  • http://{BLOCKED}ravelbiz.xyz/b7ydkq
  • http://{BLOCKED}erfit.biz/u1ohxy3c