RANSOM_BLOCKER.R00XC0OI517

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

It encrypts files found in specific folders.

Arrival Details

This Ransomware 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 Ransomware drops the following copies of itself into the affected system and executes them:

• %Application Data%\{malware name}

(Note: %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 drops the following files:

• %Application Data%\log.txt -> key for the encrypted files

(Note: %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:

• Global\ControlPanel

Autostart Technique

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

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Window = "%Application Data%\{malware name}"

Process Termination

This Ransomware terminates processes or services that contain any of the following strings if found running in the affected system's memory:

• iexplore
• iexplorer
• chrome
• firefox
• MicrosoftEdge

Other Details

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

• google.pl

It does the following:

• It connects to the URL "http://bit.ly/2razNDz" which will then be redirected to "http://www.wikihow.com/Send-Bitcoins"
• It tries to steal saved login credentials from the following browsers:
  
  • Chrome
  • Firefox
  • IE10
• It opens the following URL then attempts to login the stolen credentials:
  
  • http://facebook.com/login.php
• It lists all friends of the current account on Facebook and sends each one of them a message containing the malware and the following text:
  • To jest wiadomosc wyslana w calosci przez mojego bota
• It adds the extension ".lock" to encrypted files then renames it back to the original file name during encryption.
• It adds the extension ".unlock" to encrypted files then renames it back to the original file name during decryption.
• It opens a GUI that serves as a ransom note:

  

• It has the capability to decrypt the encrypted files once the ransom is paid.
• It adds the following registry entry to disable the CTRL key:
  
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Keyboard Layout
    • Scancode Map = "0,0,0,0,0,0,0,0,3,0,0,0,0,0,29,0,0,0,29,224,0,0,0,0"
      

Ransomware Routine

This Ransomware encrypts files found in the following folders:

• C:\Program Files (x86)
• %Program Files%
• %Application Data%
• %Desktop%
• {Removable Drives}

(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.. %Desktop% is the desktop folder, where it usually is C:\Documents and Settings\{user name}\Desktop in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\Desktop in 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 avoids encrypting files with the following strings in their file name:

• *.exe
• *.lnk
• Microsoft

It avoids encrypting files with the following strings in their file path:

• Microsoft