Analysis by: Al Victor de Leon
ALIASES:

Trojan horse Downloader.Generic13.CFSM (AVG), Trojan.Win32.Yakes.fctd (Kaspersky), TrojanDownloader:Win32/Kuluoz.D (Microsoft), Win32/TrojanDownloader.Zortob.F trojan (Nod32), Trojan.Win32.Generic!BT (Sunbelt)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 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: 180,224 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 19 Jun 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 a copy of itself in the following folders using different file names:

  • %Application Data%\{random file name}.exe

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

It leaves the following text files:

  • {Malware Path and Filename}.txt

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = "%Application Data%\{random file name}.exe"

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{random generated IP addresses}:8080

It deletes itself after execution.