Analysis by: Arvin Roi Macaraeg
ALIASES:

Worm:Win32/Macoute.A(MICROSOFT); Win32/Agent.NML worm(NOD32)

 PLATFORM:

Windows

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel: Propagates via removable drives

This Worm 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: 440,832 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 20 Aug 2019
Payload: Connects to URLs/IPs, Steals information, Drops files

Arrival Details

This Worm 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 Worm drops the following copies of itself into the affected system:

  • %Program Files%\win\msn.exe

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It drops the following files:

  • %User Temp%\iosystem.dll

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

  • "%Program Files%\win\msn.exe" pscp|%User Temp%\iosystem.dll|{BLOCKED}7.{BLOCKED}.185.184:/ecoute/spool/{User name}-{Computer Name}-{Volume information}

It creates the following folders:

  • %Program Files%\win

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • msnAPOv52552009

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
apo5 = %Program Files%\win\msn.exe <- 32BIT OS

HKEY_LOCAL_MACHINE\WOW6432Node\SOFTWARE\
Microsoft\Windows\CurrentVersion\
Run
apo5 = %Program Files%\win\msn.exe <-64Bit OS

Other System Modifications

This Worm adds the following registry entries as part of its installation routine:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\IntelliForms\Storage2

Propagation

This Worm drops the following copy(ies) of itself in all removable drives:

  • {Removable Drive}:\{folder name}.exe

Information Theft

This Worm gathers the following data:

  • System Information
  • User Name
  • Computer Name
  • Volume Information
  • Digital Product ID
  • Internet Explorer cache (Visited URL:)
  • Mozilla FireFox Credentials
  • Window Lives Credentials

Other Details

This Worm does the following:

  • It drops a copy of itself to a removable drive by getting the folder name present and using it as the filename of its copy.
  • It check the following parameters was used during the execution of the sample and terminates itself if present:
    • pscp
    • -sftp
    • -pw
    • -q
    • -batch
    • -pgp
    • -load
    • -ssh
    • -telnet
    • -rlogin
    • -raw
    • -v
    • -l
    • -L
    • -R
    • -D
    • -nc
    • -m
    • -pw
    • -P
    • -agent
    • -pagent
    • -pageant
    • -noagent
    • -nopagent
    • -nopageant
    • -x
    • -X
    • -t
    • -T
    • -N
    • -C
    • -1
    • -2
    • -i
    • -4
    • -ipv4
    • -6
    • -ipv6
  • It connects to the following URL to send its gathered information:
    • {BLOCKED}.{BLOCKED}.185.184:8829

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 15.312.06
FIRST VSAPI PATTERN DATE: 21 Aug 2019
VSAPI OPR PATTERN File: 15.313.00
VSAPI OPR PATTERN Date: 22 Aug 2019

Step 1

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 2

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Identify and terminate files detected as Worm.Win32.MACOUTE.JKA

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 4

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

 
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\IntelliForms\Storage2
    • (null)
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • apo5 = %Program Files%\win\msn.exe
  • In HKEY_LOCAL_MACHINE\WOW6432Node\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • apo5 = %Program Files%\win\msn.exe

Step 5

Search and delete this file

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %User Temp%\iosystem.dll

Step 6

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %Program Files%\win

Step 7

Scan your computer with your Trend Micro product to delete files detected as Worm.Win32.MACOUTE.JKA. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check the following Trend Micro Support pages for more information:


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