TrojanSpy.MSIL.QUIETSIEVE.SM

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

It executes commands from a remote malicious user, effectively compromising the affected system.

It connects to certain websites to send and receive information.

Arrival Details

This Trojan Spy 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 Spy drops the following files:

• %AppDataLocal%\IconsCache.db -> contains hashed equivalents of the unique files to steal
• %User Temp%\SymbolSourceSymbols\icons\{current date in YYYY-MM-DD-HH-MM format}.jpg -> screenshot of the current state of the machine

(Note: %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It creates the following folders:

• %User Temp%\SymbolSourceSymbols\icons

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

• Global\{Random characters}

Backdoor Routine

This Trojan Spy executes the following commands from a remote malicious user:

• Remote code execution
• Capture screenshots

Information Theft

This Trojan Spy gathers the following data:

• Computer name
• User name
• Volume Serial Number

Other Details

This Trojan Spy connects to the following website to send and receive information:

• https://{BLOCKED}.{BLOCKED}.109.164/{Random alphanumeric characters}

It does the following:

• It steals files with the following extensions:
  • .doc
  • .docx
  • .xls
  • .rtf
  • .odt
  • .txt
  • .jpg
  • .pdf
• It steals files with the following extensions if they are seen on folders with 'Desktop' or 'Documents' in its folder name:
  • .7z
  • .rar
  • .zip