Trojan-Ransom.Win32.Purga.be (Kaspersky), Ransom.Scarab (Malwarebytes), Trojan:Win32/Skeeyah.A!rfn (Microsoft)
Windows
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 lowers the security setting of Internet Explorer.
It deletes itself after execution.
It encrypts files with specific file extensions. 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:
(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.)
It adds the following processes:
Autostart Technique
This Ransomware adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
{45E73A27-D16C-4EDB-ADE8-0C069E54AF30} = "%Application Data%\sevnz.exe"
Web Browser Home Page and Search Page Modification
This Ransomware lowers the security setting of Internet Explorer.
Download Routine
This Ransomware accesses the following websites to download files:
Other Details
This Ransomware deletes itself after execution.
Ransomware Routine
This Ransomware encrypts files with the following extensions:
It renames encrypted files using the following names:
It drops the following file(s) as ransom note:
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 2
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 3
Identify and terminate files detected as RANSOM_SCARAB.A
Step 4
Delete this registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
Step 5
Search and delete this file
Step 6
Reset Internet security settings
Step 7
Scan your computer with your Trend Micro product to delete files detected as RANSOM_SCARAB.A. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
Step 8
Restore encrypted files from backup.
NOTES:
Do this as Step 9 of the solution process:
Enable Windows Recovery Option
1. Run cmd.exe as administrator
2. Type "bcdedit /set {default} recoveryenabled Yes" then press Enter
3. Type "bcdedit /set {default} bootstatuspolicy displayallfailures", then press Enter.