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TSPY_BEBLOH.YMNON

September 05, 2018
 Analysis by: Byron Jon Gelera
 Modified by: Henry Alarcon Jr.
 ALIASES:

Trojan.Win32.Yakes.wxoh (Kaspersky), Trojan:Win32/Tiggre!rfn (Microsoft)

 PLATFORM:

Windows

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

  • Threat Type: Trojan Spy

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware, Downloaded from the Internet

This Trojan Spy arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size:

337,920 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

07 Aug 2018

Payload:

Connects to URLs/IPs, Downloads files, Drops files, Collects system information

Arrival Details

This Trojan Spy 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 Spy drops the following files:

  • %Application Data%\{random string}.lnk -> executes %Program Files%\Windows NT\{random filename}.exe
      (Note: Creation of this file is triggered when the affected system is shutting down, appends parameter "-autorun" to executed copy)

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

It drops the following copies of itself into the affected system:

  • %Program Files%\Windows NT\{random filename}.exe
      (Note: Creation of this copy is triggered when the affected system is shutting down)

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

It adds the following processes:

  • explorer.exe

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

  • Global\ Uz{Random Hex}

It injects codes into the following process(es):

  • The created "explorer.exe" by this malware

Autostart Technique

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

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

    (Note: Creation of this registry entry is triggered when the affected system is shutting down)

Other System Modifications

This Trojan Spy adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\{Random Key}

It adds the following registry entries:

HKEY_CURRENT_USER\Software\{random key}
(Default) = {Hex Values}

Download Routine

This Trojan Spy saves the files it downloads using the following names:

  • %User Temp%\{random filename}.exe

(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, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, and 8.)

Information Theft

This Trojan Spy gathers the following data:

  • Machine Name
  • OS Information (Version, Product ID, Name, Install Date)
  • Explorer File Information
  • Volume Serial Number
  • Network Configuration (IP address, Socket, Ports)
  • Keyboard Layout
  • CPU Information
  • Video BIOS Version

Stolen Information

This Trojan Spy sends the gathered information via HTTP POST to the following URL:

  • https://{BLOCKED}ola.com/auth/?tver={value}&vcmd={value}&cc={value}&hh={hex values}&ipcnf={IP address}+&sckport={value}&pros={value}&keret={value};&email={value}

Other Details

This Trojan Spy connects to the following URL(s) to check for an Internet connection:

  • www.google.com

It connects to the following website to send and receive information:

  • https://{BLOCKED}ola.com/auth/
  • {Random Generated Domain}.com
  • {Random Generated Domain}.net

It does the following:

  • Updates Itself.
  • Does not execute its malicious routine if it detects it runs on a simulated environment:
    • Running on a VMWare or VirtualBox Environment
    • Process has a sbiedl.dll module
    • Processor name contains the string "Xeon"
    • File path contains the following strings:
      • \SAMPLE
      • VIRUS
      • SANDBOX
  • Deletes cache files for Google Chrome and Mozilla Firefox.
  • This malware does any of the following based on the reply of its C&C server:
    • Sleep and wait for the next reply
    • Receive download URL to download other possibly malicious files
  • The file names used for its dropped copy may contain the following strings combined with random characters:
    • def
    • dns
    • exec
    • hlp
    • logon
    • mem
    • mixer
    • mon
    • pack
    • play
    • setup
    • srv
    • user
    • video
    • win
    • It may also use a purely random set of characters as filename for its dropped copy.

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

13.840.05

FIRST VSAPI PATTERN DATE:

13 Dec 2017

VSAPI OPR PATTERN File:

13.841.00

VSAPI OPR PATTERN Date:

14 Dec 2017

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 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

Restart in Safe Mode

[ Learn More ]

Step 4

Delete this registry key

[ 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\{random key}
    • (Default) = {Hex Values}

Step 5

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\Windows\CurrentVersion\Run
    • {random string} = "%Application Data%\{random string}.lnk"

Step 6

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%\{random filename}.exe
  • %Application Data%\{random string}.lnk
  • %Program Files%\Windows NT\{random filename}.exe

Step 7

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_BEBLOH.YMNON. 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 this Knowledge Base page for more information.


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