How HVNC Works

[chushpan]

What is HVNC?​

HVNC (Hidden Virtual Network Computing) is a remote access technology that allows you to control a remote computer through a graphical interface, but unlike traditional remote access tools (such as RDP or VNC), HVNC hides its activity from the user on the target device. This makes HVNC popular among attackers to perform covert actions on infected systems.

HVNC is often used for illegal purposes, such as:

• Data theft.
• Carrying out fraudulent transactions (for example, making payments through the victim's browser).
• Bypassing security systems that monitor user activity.

How does HVNC work?​

HVNC works by creating a "hidden" remote access session. Instead of using the user's standard desktop, HVNC creates a virtual display that is not visible on the target device's screen. Here are the basic steps:

1. Installation of HVNC​

1. Download and run:
   • The attacker installs HVNC on the target device (usually via malware or exploits).
   • HVNC can be embedded as an executable or a library.
2. Creating a virtual display:
   • HVNC uses special drivers (such as VNC or X-server) to create a virtual display.
   • This display is completely isolated from the user's physical monitor.

2. Connecting to HVNC​

1. Client connection:
   • The attacker connects to the HVNC server via an IP address or domain name.
   • Connection can be made via the Internet or a local network.
2. Displaying a virtual desktop:
   • On the attacker's side, a window opens showing the virtual desktop of the target device.
   • All actions occur "in the background", without being displayed on the user's physical screen.

3. Hidden work​

1. Isolated session:
   • HVNC operates independently of an active user session.
   • Even if the user is actively working on the computer, he does not see the actions of the intruder.
2. Bypassing activity detectors:
   • Many security systems monitor mouse and keyboard activity on a physical device. Since HVNC runs on a virtual display, such systems do not notice it.

4. Completing tasks​

1. Automation of actions:
   • An attacker can automate actions such as entering data into forms, clicking buttons, or executing commands.
2. User disguise:
   • HVNC can emulate real user actions (e.g. mouse movements, text input) to bypass behavior analysis systems.
3. Data theft:
   • An attacker can gain access to files, browsers, credentials, and other sensitive data.

HVNC Usage Example​

Scenario: Bank Card Fraud​

1. The attacker infects the victim's computer with malware containing HVNC.
2. HVNC creates a hidden session on the victim's computer.
3. The attacker connects to HVNC and opens the victim's browser.
4. He enters the stolen credentials and makes payments without being noticed.
5. The victim does not suspect anything, as the actions take place in the background.

Advantages of HVNC​

1. Stealth:
   • HVNC runs in the background without appearing on the physical screen.
   • The user does not notice any signs of hacking.
2. Bypassing security systems:
   • HVNC helps bypass systems that monitor mouse and keyboard activity.
3. Flexibility:
   • Can be used for a variety of tasks, from data theft to automation of actions.
4. User independence:
   • HVNC works even if the user is actively using the computer.

Disadvantages of HVNC​

1. Illegal purposes:
   • HVNC is most often used for illegal activities, making it a dangerous tool.
2. Resource intensity:
   • Creating a virtual display and delivering graphics requires significant resources.
3. Network dependency:
   • HVNC requires a stable internet connection to transfer data.
4. High risk of detection:
   • Modern antivirus and security systems can detect HVNC.

HVNC Protection​

1. Antivirus software:
   • Use modern antivirus software that can detect and block HVNC.
2. System update:
   • Update your operating system and programs regularly to eliminate vulnerabilities.
3. Firewall:
   • Configure your firewall to block unauthorized connections.
4. Activity monitoring:
   • Use tools to monitor processes and network connections.
5. Education:
   • Be careful when opening suspicious files or links.

Conclusion​

HVNC is a powerful but dangerous tool that can be used for both legitimate and illegitimate purposes. Due to its stealth and ability to bypass security systems, HVNC is often used by attackers to steal data and conduct fraudulent transactions. To protect yourself from HVNC, it is important to use reliable antivirus software, regularly update your system, and monitor the security of your device.

 

[Man]

How does HVNC (Hidden Virtual Network Computing) work?​

HVNC is a hidden version of classic VNC (Virtual Network Computing) that allows an attacker to remotely control the victim's computer without a visible GUI (connection window, tray icon, etc.). Often used in cyber attacks for hidden control over the system.

1. HVNC Working Principle​

1.1. Main Features​

• Stealth:
  • Does not create visible windows.
  • Disguises itself as system processes (for example, svchost.exe).
• Functionality:
  • Full access to the desktop.
  • Input recording (keylogging).
  • Bypass UAC (User Account Control).
• Methods of implementation:
  • Through exploits (e.g. phishing emails).
  • Injection into legitimate processes.

1.2. Technical implementation​

1. Implementation into the system:
   • Through malware, macros in Office, or vulnerabilities (such as EternalBlue).
2. Starting the HVNC server:
   • Embedded into process memory (eg explorer.exe).
3. Connection of the attacker:
   • The HVNC client connects to the infected PC via TCP/IP (often via Tor or a proxy).
4. Hidden mode:
   • Runs in the background and is not displayed in the task manager as a separate application.

2. Difference between HVNC and classic VNC​

Criterion	HVNCC	Regular VNC
Visibility	Hidden, no GUI	The connection window is visible
Detection	Complex (antiviruses often miss)	Easy to detect
Usage	Cyber attacks, hidden access	Legal remote access

3. How to detect HVNC?​

3.1. Signs of infection​

• Unexplained network activity (suspicious TCP connections).
• Unusual processes in RAM (for example, svchost.exe with abnormal rights).
• High CPU/GPU load when system is idle.

3.2. Analysis tools​

• Process Hacker - Find hidden injections.
• Wireshark - monitoring suspicious traffic.
• Volatility (for memory dumps).

4. Examples of HVNC use in attacks​

• Banking Trojans (e.g. TrickBot, Emotet) – hidden access to banking sessions.
• Espionage is the theft of corporate data.
• Ransomware - preparing to encrypt files.

5. HVNC Protection​

1. Antiviruses with behavioral analysis:
   • Kaspersky, CrowdStrike (can detect injections).
2. Limitation of user rights:
   • Prevents running unsigned software.
3. Network Monitoring:
   • SIEM systems (e.g. Splunk).
4. OS update:
   • Patches to close vulnerabilities.

Conclusion​

1. HVNC is a hidden backdoor for complete control over your PC.
2. Used by hackers for espionage and cyber fraud.
3. It is difficult to detect, but possible through process and network monitoring.

If you are an administrator, set up anomaly analysis in the system. If you accidentally launched a suspicious file, check your PC using emergency LiveCDs (for example, Kaspersky Rescue Disk).

Need specific detection methods? Write!