BKDR_LUMINOSITY.Z

 Analysis by: Jennifer Gumban

 PLATFORM:

Windows

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Spammed via email

This backdoor arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

It connects to a website to send and receive information.

  TECHNICAL DETAILS

File Size:

3,803,648 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

23 Nov 2016

Payload:

Connects to URLs/IPs, Logs keystrokes, Launches DoS/DDoS attacks, Terminates processes

Arrival Details

This backdoor arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

Installation

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

  • %Program Files%\Client\client.exe
  • {drive letter}:\{malware name}.exe
  • %Application Data%\ccleaners.exe

(Note: %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.. %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming 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.)

It creates the following folders:

  • %Program Files%\Client
  • %Application Data%\Monitor
  • %Application Data%\Monitor\Guard - folder contains guarded files
  • %Application Data%\Monitor\Files
  • %Application Data%\Monitor\Logs - folder contains logs of keystrokes

(Note: %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.. %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming 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.)

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

  • 5c625b47725859cc074e8bcb8417ac99ee68410d

It injects itself into the following processes as part of its memory residency routine:

  • explorer.exe
  • smss.exe
  • csrss.exe
  • wininit.exe

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
Client Monitor = ""%Program Files%\Client\client.exe" -a /a"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Client Monitor = ""%Program Files%\Client\client.exe" -a /a"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{malware name} = %Application Data%\ccleaners.exe

Other System Modifications

This backdoor adds the following registry entries:

HKEY_CURRENT_USER\Software
WPLvJO2R9ufWFSi2N4ZWQQ== = "3oUPYe3wrjkmhnX+vuMdhyPo6fQvbtpFBg8XTninP0Fp15MIMzl1zyXO3skB+WQp"

HKEY_CURRENT_USER\Software\mJx/uZUSbRzkuLX1v
bfjg== = "cwKeWgof3ueENirKrTN1ZQ=="

Backdoor Routine

This backdoor connects to the following websites to send and receive information:

  • free-125-81.{BLOCKED}orksit.net:1142
    ip: {BLOCKED}.{BLOCKED}.125.81

Other Details

This backdoor does the following:

  • This backdoor is capable of the following:
    • DDOS Attack
    • Create/Kill Process
    • Kill/Update Bot
    • Create/Modify/Delete Files
    • Create/Modify/Delete Directories
    • Download/Upload Files
    • Execute Files
    • Start/Stop Shell
    • Guard Files
    • Log Keystroke
    • Record Audio
    • Record Camera/Webcam
    • Send Emails

  SOLUTION

Minimum Scan Engine:

9.800

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

Restart in Safe Mode

[ Learn More ]

Step 3

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\RunOnce
    • Client Monitor = ""%Program Files%\Client\client.exe" -a /a"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Client Monitor = ""%Program Files%\Client\client.exe" -a /a"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • {malware name} = %Application Data%\ccleaners.exe
  • In HKEY_CURRENT_USER\Software
    • WPLvJO2R9ufWFSi2N4ZWQQ = = = "3oUPYe3wrjkmhnX+vuMdhyPo6fQvbtpFBg8XTninP0Fp15MIMzl1zyXO3skB+WQp"
  • In HKEY_CURRENT_USER\Software\mJx/uZUSbRzkuLX1v
    • bfjg = = = "cwKeWgof3ueENirKrTN1ZQ=="

Step 4

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%\Client
%Application Data%\Monitor
%Application Data%\Monitor\Guard
%Application Data%\Monitor\Files
%Application Data%\Monitor\Logs

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_LUMINOSITY.Z. 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.

Step 6

Scan your computer with your Trend Micro product to delete files detected as BKDR_LUMINOSITY.Z. 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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