RANSOM_DARKENCRYPTOR.A

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 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.

Installation

This Ransomware adds the following folders:

• %User Temp%\{8 random values}

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp 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 copies of itself into the affected system and executes them:

• %User Temp%\{8 random values}\{6 random values}.exe

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp 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.)

Other System Modifications

This Ransomware sets the system's desktop wallpaper to the following image:

Download Routine

This Ransomware accesses the following websites to download files:

• https://{BLOCKED}er.com/?frsemg6xcg
• https://{BLOCKED}er.com/?sqk1iwb38v

It saves the files it downloads using the following names:

• %User Temp%\tdewallpaper.png ← used as wallpaper
• %User Temp%\winui.exe

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp 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.)

Other Details

This Ransomware does the following:

• Execute the copy with the argument --run

Ransomware Routine

This Ransomware encrypts files with the following extensions:

• .png
• .jpg
• .jpeg
• .bmp
• .mp3
• .wav
• .mp4
• .mov
• .avi
• .pdn
• .exe
• .zip
• .doc
• .docx
• .docm
• .ppx
• .ppm
• .otf"
• .txt
• .html
• .css
• .xhtml
• .xml
• .obj
• .js
• .java
• .cs
• .c
• .cpp
• .php
• .bat

It encrypts files found in the following folders:

• Personal
• Pictures
• Videos
• Music
• Desktop
• Downloads
• E:\
• F:\
• H:\
• I:\

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

• .tdelf

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

• %User Temp%\tdewallpaper.png

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp 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.)

NOTES:

This ransomware displays the following fake error message: