arrow_back
search
close

BKDR_MATSNU.JB

April 17, 2013
 Analysis by: Jaime Benigno Reyes
 ALIASES:

Trojan:Win32/Matsnu (Microsoft), Trojan.Win32.Yakes.cowi (Kaspersky)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • 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 executes then deletes itself afterward.

  TECHNICAL DETAILS

File Size:

164,864 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

12 Apr 2013

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:

  • %Application Data%\{random}\{random}.exe
  • %User Profile%\{random}\{random}.exe
  • %User Temp%\{random}\{random}.exe
  • %User Temp%\{random}.pre - deleted afterwards

(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.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

It executes then deletes itself afterward.

It injects codes into the following process(es):

  • svchost.exe
  • ctfmon.exe
  • explorer.exe

Autostart Technique

This Trojan creates the following registry entries to enable automatic execution of dropped component at every system startup:

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = "%%User Profile%\{random}\{random}.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = "%User Temp%\{random}\{random}.exe"

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}ieg.com/inbox.php
  • http://{BLOCKED}-gt.com/inbox.php
  • http://{BLOCKED}zxrz.com/inbox.php
  • http://{BLOCKED}ect-proxy.com/inbox.php
  • http://{BLOCKED}lines.com/inbox.php
  • http://{BLOCKED}nline.com/inbox.php
  • http://{BLOCKED}olderxx.com/inbox.php
  • http://{BLOCKED}bspace-apo.com/inbox.php