RANSOM_NATAS.J

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 connects to certain websites to send and receive information. It is capable of encrypting files in the affected system.

It encrypts files with specific file extensions. It encrypts files found in specific folders. It drops files as ransom note.

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.

Download Routine

This Ransomware accesses the following websites to download files:

• http://www.{BLOCKED}activator-registration.nl/Tools/UNLOCK.rar
• http://i.{BLOCKED}r.com/L6xzvLS.jpg

It saves the files it downloads using the following names:

• %User Profile%\ransom.jpg - Desktop Wallpaper
• {malware path}\UNLOCK.rar - Unlocker

(Note: %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.)

Other Details

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

• https://www.google.com/

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

• http://www.{BLOCKED}activator-registration.nl/fa2/write.php?info=?computer_name={machine name}&userName={user name}&password={password}&allow=ransom

It does the following:

• Changes the Desktop wallpaper to:
  
• Displays a ransom note READ_IT.txt:
  

It is capable of encrypting files in the affected system.

Ransomware Routine

This Ransomware encrypts files with the following extensions:

• .txt
• .jar
• .exe
• .dat
• .contact
• .settings
• .doc
• .docx
• .xls
• .xlsx
• .ppt
• .pptx
• .odt
• .jpg
• .png
• .csv
• .py
• .sql
• .mdb
• .sln
• .php
• .asp
• .aspx
• .html
• .htm
• .xml
• .psd
• .pdf
• .dll
• .c
• .cs
• .mp3
• .mp4
• .f3d
• .dwg
• .cpp
• .zip
• .rar
• .mov
• .rtf
• .bmp
• .mkv
• .avi
• .apk
• .lnk
• .iso
• .7-zip
• .ace
• .arj
• .bz2
• .cab
• .gzip
• .lzh
• .tar
• .uue
• .xz
• .z
• .001
• .mpeg
• .mpg
• .core
• .crproj
• .pdb
• .ico
• .ico
• .pas
• .db
• .torrent
• .asf
• .waw
• .jpeg
• .docm
• .wmv
• .wav
• .ac3
• .raw
• .cms
• .js

It encrypts files found in the following folders:

• %User Profile%\Desktop
• %User Profile%\Links
• %User Profile%\Contacts
• %User Profile%\Documents
• %User Profile%\Downloads
• %User Profile%\Pictures
• %User Profile%\Music
• %User Profile%\OneDrive
• %User Profile%\Saved Games
• %User Profile%\Favorites
• %User Profile%\Searches
• %User Profile%\Videos

(Note: %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.)

It appends the following extension to the file name of the encrypted files:

• .locked

It drops the following file(s) as ransom note:

• %Desktop%\READ_IT.txt

(Note: %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.)