RANSOM

RANSOM is the Trend Micro detection for most ransomware. Most ransomware are known to restrict the user from fully accessing the system. It also encrypts files and demands a ransom to be paid in order to decrypt or unlock the infected machine.

Ransomware infects computers through various means. Most of ransomware come as a macro or JavaScript attachment in spammed email. Some are delivered as a link, also in spammed email. Others are delivered by exploit kits. Some others are delivered via malvertisements or compromised websites.

To prevent ransomware, users should use protection that also covers against spam and malicious links. Also, make sure to regularly create backup copies of all important files.

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users. It may be unknowingly downloaded by a user while visiting malicious websites. It may arrive using one or multiple arrival methods.

It disables Task Manager, Registry Editor, and Folder Options.

Arrival Details

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

It may be unknowingly downloaded by a user while visiting malicious websites.

It arrives via the following means:

• Exploit kits
• Compromised sites
• Malvertisements

Installation

This Trojan drops the following files:

• {malware path}\{malware name}.mp3

It drops the following copies of itself into the affected system:

• %Application Data%\Realtec\Realtecdriver.exe
• %Application Data%\{random}\{random}.exe
• %System%\{random}.exe

(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.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

It creates the following folders:

• %Application Data%\Realtec
• %Application Data%\{random}

(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.)

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
GoogleChrome = "{malware path}\{malware name}.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Microsoft Updater = "{malware path}\{malware name}.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Realtecdriver = "%Application Data%\Realtec\Realtecdriver.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
B0B2D6E3 = "%Application Data%\{random}\{random}.exe"

It modifies the following registry entries to ensure it automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Userinit = "%System%\userinit.exe,%System%\{random}.exe,"

(Note: The default value data of the said registry entry is %System%\userinit.exe,.)

It adds the following Image File Execution Options registry entries to automatically execute itself whenever certain applications are run:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
{application name}
Debugger = "P9KDMF.EXE"

Other System Modifications

This Trojan adds the following registry keys as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
{application name}

It creates the following registry entry(ies) to disable Task Manager, Registry Tools and Folder Options:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableRegistryTools = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableRegedit = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
system
DisableRegedit = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
system
DisableTaskMgr = "1"

It deletes the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\SafeBoot

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\SafeBoot\Minimal

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\SafeBoot\Network

Other Details

This Trojan connects to the following possibly malicious URL:

• {BLOCKED}.{BLOCKED}.229.104
• {BLOCKED}secenter.org
• http:// {BLOCKED}a.{BLOCKED}1.ru /Silence/read.php?nm=32432
• http://{BLOCKED}.{BLOCKED}.1.191/admNEW/lic.php
• http://{BLOCKED}a.com/a.php?id=B0B2D6E3584E49570050&cmd=img
• http://{BLOCKED}o.com/a.php?id=B0B2D6E3584E49570050&cmd=imgw
• http://{BLOCKED}a.com/04/a.php?id=B0B2D6E3584E49570050&cmd=img
• http://{BLOCKED}forum.com/04/a.php?id=B0B2D6E3584E49570050&cmd=img
• http://ww25.{BLOCKED}forum.com/04/a.php?id=B0B2D6E3584E49570050&cmd=img
• http://{BLOCKED}fo.com/04/a.php?id=B0B2D6E3584E49570050&cmd=img