TROJ_CRYPT.VUV

 Modified by: Homer Pacag

 ALIASES:

RDN/Ransom!ek (McAfee); Trojan.Smoaler (Symantec); Trojan-Ransom.Win32.Foreign.ldqz (Kaspersky); Troj/Agent-AIYA (Sophos); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse Crypt3.APJK (AVG)

 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.

It deletes itself after execution.

  TECHNICAL DETAILS

File Size:

113,152 bytes

File Type:

EXE

Initial Samples Received Date:

01 Oct 2014

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 the following copies of itself into the affected system:

  • %User Temp%\winlogin.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.)

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
winlogin = "%User Temp%\winlogin.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Active Setup\Installed Components\05F16C88-71D3-42C1-BB4F-E9BAF7DB4A9E
cfg = "{random characters}"

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}zip.com
  • {BLOCKED}.218.205
  • {BLOCKED}60.200
  • {BLOCKED}.221.20

It deletes itself after execution.