RANSOM_SAD.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 connects to certain websites to send and receive information. It gathers information and reports it to its servers. It is capable of encrypting files in the affected system.

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 drops the following copies of itself into the affected system:

• {Drive Letter}:\Picture.exe
• %User Temp%\{Malware Filename}{Random Letter/s}.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.)

It drops the following file(s)/component(s):

• %User Temp%\id.txt - contains the Generated GUID for the appended extension of the ransomware

(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 changes the desktop wallpaper by modifying the following registry entries:

HKEY_CURRENT_USER\Control Panel\Desktop
Wallpaper = %Desktop%\_HELPME_DECRYPT_.png

Other Details

This Ransomware connects to the following website to send and receive information:

• http://database1234.{BLOCKED}d.net/cry.php?hwid={Generated GUID}%20&osname={OS Name}l%20&pcname={Machine Name}&key={Generated Key}

It gathers the following information and reports it to its servers:

• Generated GUID
• OS Name
• Machine Name
• Generated Key

It is capable of encrypting files in the affected system.

Ransomware Routine

This Ransomware encrypts files found in the following folders:

• {All Available Drives}:\
• %User Profile%\Documents
• %User Profile%\Downloads
• %User Profile%\Pictures
• %User Profile%\Music
• %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 avoids encrypting files found in the following folders:

• {Filename}.exe
• {Filename}.dll
• %System Root%
• %Desktop%

(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %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 appends the following extension to the file name of the encrypted files:

• .{Generated GUID}

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

• %Desktop%\_HELPME_DECRYPT_.html
• %Desktop%\_HELPME_DECRYPT_.txt
• %Desktop%_HELPME_DECRYPT_.hta

(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.)

NOTES:

This ransomware displays the following: