RANSOM_SPORA.THCOK

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

It is capable of encrypting files in the affected system.

Arrival Details

This Trojan 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 Trojan drops a copy of itself in the following folders using different file names:

• {Fixed and Removable Drive Letter}:\{Random Values}.exe -> set attributes to Hidden
• %User Temp%\{Random Values}.exe - set attributes to Hidden
• %Desktop%\{Random Values}.exe -> set attributes to Hidden

(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.. %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 drops the following files:

• {Fixed and Removable Drive Letter}:\{Shortcut files with the filename of every folder in the removable and fixed drive}
  • The malware creates these shortcut files in order to trick the user due to its folder icon and legit filenames.
  • The target path of these shortcuts is set to: %System%\cmd.exe /c start explorer.exe “{folder name - where original files are stored}” & type "{Random Values}.exe - dropped copy of the malware" > "%temp%\{Random Values}.exe - dropped copy of the malware" && "%temp%\{Random Values}.exe - dropped copy of the malware"
• %Application Data%\{10 digit number}
• %Application Data%\{Unique ID}.html -> Ransom Note
• %Application Data%\Microsoft\Windows\Templates\{Unique ID}.html -> Ransom Note
• %Desktop%\{Unique ID}.html -> Ransom Note
• %User Profile%\{Unique ID}.html -> Ransom Note
• %User Profile%\Favorites\{Unique ID}.html -> Ransom Note
• %User Startup%\{Unique ID}.html -> Ransom Note, to enable automatic execution at system startup
• %AppDataLocal%\VirtualStore\{Unique ID}.html -> Ransom Note

(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.. %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.. %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.. %User Startup% is the current user's Startup folder, which is usually C:\Documents and Settings\{user}\Start Menu\Programs\Startup on Windows 2000 and XP, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows Vista, 7, and 8.. %AppDataLocal% is the Application Data folder found in Local Settings, where it is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local 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 Trojan is capable of encrypting files in the affected system.