RANSOM_CRYONI.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 deletes itself after execution.

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 files:

• %User Temp%\qfjgmfgmkj.tmp

(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 and executes the following files:

• %User Temp%\hjkhkHUhhjp.bat -> used to delete itself and the malware

(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 adds the following processes:

• vssadmin.exe Delete Shadows /Quiet /All -> deletes shadow copies

Other Details

This Ransomware deletes itself after execution.

Ransomware Routine

This Ransomware encrypts files found in the following folders:

• All Drives
• %Desktop%

(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.)

It avoids encrypting files with the following strings in their file path:

• windows
• Microsoft
• Microsoft Help
• Windows App Certification Kit
• Windows Defender
• ESET
• COMODO
• Windows NT
• Windows Kits
• Windows Mail
• Windows Media Player
• Windows Multimedia Platform
• Windows Phone Kits
• Windows Phone Silverlight Kits
• Windows Photo Viewer
• Windows Portable Devices
• Windows Sidebar
• WindowsPowerShell
• Temp
• NVIDIA Corporation
• Microsoft.NET
• Internet Explorer
• Kaspersky Lab
• McAfee
• Avira
• spytech software
• sysconfig
• Avast
• Dr.Web
• Symantec
• Symantec_Client_Security
• system volume information
• AVG
• Microsoft Shared
• Common Files
• Outlook Express
• Movie Maker
• Chrome
• Mozilla Firefox
• Opera
• YandexBrowser
• ntldr
• wsus
• Wsus

It avoids encrypting files found in the following folders:

• A:\

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

• .oni

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

• {Folder containing encrypted files}\!!!README.html