Security and compliance

With great power comes responsibility. VNC Connect is built from the ground up with security in mind, to balance the access and control you need with the complete privacy that regulations require.

Our fundamental security principles

Principle 1

You don't have to trust RealVNC as a company to trust our software and services

Principle 2

We do not store your session data, and it cannot be decrypted now or in the future

Principle 3

Every connection is treated as though it is made in a hostile environment

Principle 4

The owner of the remote computer ultimately decides who is able to connect

Frequently asked questions


  • Who can discover my computers?

    Only people you invite in to your team can sign in to VNC Viewer and discover your computers. (So only invite people you trust!) Note with a Professional or Enterprise subscription you can further restrict discovery by assigning permissions on the Computers page of your RealVNC account to precisely match computers with people.

    If a person cannot discover your computers then they cannot possibly establish cloud connections to them; there’s no way to bypass our discovery service.

    Note that if you have an Enterprise subscription and intend to establish direct connections, it is possible for a malicious entity to sniff the port you’ve opened in the remote computer’s firewall (5900 TCP by default). It’s much safer to use cloud connectivity over the Internet!

  • Who can connect to my computers?

    Only people in your team with permission to discover computers can sign in to VNC Viewer and attempt to connect to them.

    To complete a connection, a team member must still enter the credentials expected by VNC Server running on that computer.

    So computers are protected twice, by independent password mechanisms: the RealVNC account system controls discovery, and the VNC Server authentication scheme polices connectivity.

  • How can I be sure I’m connecting to the right computer?

    VNC Server has a unique digital signature designed to help keep you safe online. This is a hexadecimal representation of a 2048-bit RSA public key hash, which (in the real world) means it’s a six-word memorable catchphrase, for example “Omega Chris Chicago. Alabama arrow network”. Download our whitepaper for the technical details.


    When you connect, the RealVNC services automatically verify this identity, and VNC Viewer additionally prompts you to check it yourself. If you’re subsequently warned that the catchphrase has changed, it might indicate that someone has tampered with the computer, or is trying to intercept your connection (a ‘man-in-the-middle’ attack).

    Note that if you have an Enterprise subscription and establish a direct connection, then the RealVNC services cannot perform this automatic check, so you should do so yourself.

  • Is it mandatory to authenticate to VNC Server?

    Yes. VNC Server password-protection is turned on permanently.

    VNC Server's authentication scheme is completely separate from your RealVNC account, so even if a malicious entity learns your account credentials and signs in to VNC Viewer as you, they still cannot connect. And if they try to guess the VNC Server password (a 'brute force' or 'dictionary' attack), they’ll be blacklisted.

    Note you can ask VNC Viewer to remember VNC Server passwords for you as a convenience. If you do, we recommend setting a master password on VNC Viewer's Preferences > Privacy page.

  • What’s the strongest VNC Server authentication scheme available?

    If you have a Home subscription, there’s only one VNC Server authentication scheme. Make sure the password you’re prompted to create when you install VNC Server is difficult to guess, and keep it safe. You must specify at least 6 case-sensitive letters, numbers, and special characters such as !@*#&, though we recommend more.

    If you have a Professional or Enterprise subscription, then by default VNC Server is integrated into the credentialing mechanism of the remote computer, so you don’t have to create or remember yet another password. Simply connect using the same user name and password you normally use to log on to your user account on that computer. You can register other users with VNC Server so they can connect using their own familiar system account credentials if you wish.

    If you have a Professional or Enterprise subscription, you can change the default system authentication scheme to specify multi-factor authentication for VNC Server.

    If you have an Enterprise subscription and a suitable corporate network, you can set up single sign-on (SSO) for VNC Server.

  • If I choose to remember VNC Server passwords, where are they stored?

    The first time you use VNC Viewer to connect to a computer, you must enter the password expected by VNC Server.

    Subsequently, you can ask VNC Viewer to remember this password so you don’t have to enter it each time. If you do, we additionally recommend setting a master password for VNC Viewer in case you lose or share your device:


    VNC Viewer stores passwords locally and never syncs them to other devices via our cloud service (so you’ll have to remember them on each device you connect from). Download our whitepaper for the technical details.

    Note you can sign out remotely from all VNC Viewer devices if you think your account has been compromised. Sign in to your RealVNC account and navigate to the Security page.

  • What do my RealVNC account credentials control?

    Your RealVNC account credentials (email address and password) are important; please do not share them with anyone! You need them them each time you:

    • Sign in online to manage computers, people, billing and more.
    • Sign in to VNC Server to apply your subscription.
    • Sign in to VNC Viewer to discover team computers and sync your address book.

    Your account password must be at least 8 characters long and should not be the same as a VNC Server password, nor that of any other online service you use.

    Note that if you invite someone in to your team to share remote access, that person sets up their own RealVNC account in the process of accepting your invitation. They never need to know your RealVNC account credentials.

    We recommend enabling 2–step verification on the Security page of your RealVNC account.

  • Is multi-factor authentication (2FA) available?


    For your RealVNC account, we recommend enabling 2-step verification on the Security page. Every time you sign in, you'll be prompted to enter a unique TOTP code generated by the Google Authenticator app on a convenient mobile device.

    If you have a Professional or Enterprise subscription, we recommend setting up multi-factor authentication for VNC Server.

  • Is there an audit trail of connection attempts?

    Yes. VNC Server automatically logs audit information, so you have a complete record of who’s connected, when, from where and, if the user successfully authenticated, the time of disconnection (so you can calculate session length).

    The storage destination for this information differs depending on the platform and VNC Server mode. General information about logging is available here.

    Note you can quickly dial up the logs to debug level if you need.

  • Are there any known security vulnerabilities?

    Security is at the heart of our business so we publish information about potential vulnerabilities as soon as we find them.

  • How do I set up VNC Connect for maximum security?

    Follow the instructions below. Note if you have an Enterprise subscription, you can perform bulk operations on computers remotely using policy. This has the additional security benefit of locking down computers and preventing change by users.

    1. Buy an Enterprise subscription.
    2. Choose a complex RealVNC account password and turn on 2-step verification on the Security page.
    3. If you wish to share remote access, only invite people you trust in to your team.
    4. Insist these people choose complex passwords for their own RealVNC accounts, and also turn on 2-step verification.
    5. Assign permissions on the Computers page of your RealVNC account to restrict discovery appropriately.
    6. For each remote computer:
    7. Review connection logs on a regular basis.


  • Are remote control sessions encrypted?

    Yes, always.

    If you have a Home or Professional subscription, connections are encrypted end-to-end using 128-bit AES, 2048-bit RSA keys and perfect forward secrecy, so sessions are entirely private to you now and in the future.

    If you have an Enterprise subscription, you have the option to upgrade to 256-bit AES.

  • Can I make sessions view-only?

    Yes. You can make sessions view-only for everyone on VNC Server’s Options > Users & Permissions page:


    If you have a Professional or Enterprise subscription, you can exercise more fine-grained control and make sessions view-only just for some.

    Alternatively, VNC Viewer users can choose to make their own sessions view-only from VNC Viewer's Properties dialog or mobile app toolbar.

  • Can I approve people at the time they connect?

    Yes. If you will be physically present at the computer when people connect, you can configure VNC Server to notify you and approve or reject each connection:


    To do this, turn on Show accept/reject prompt for each connection on VNC Server's Options > Connections page:


  • How do I disconnect people, or prevent them connecting?

    You can disconnect all users immediately:


    ...or individually from VNC Server's Information Center dialog.

    By default, users can connect concurrently. You can specify that only one user connects at a time.

    By default, if a connecting user fails to authenticate properly five times in a row, their computer is blacklisted. You can lower this threshold for additional protection from brute-force or port scanning attacks.

    If you have an Enterprise subscription and establish direct connections, you can filter incoming computers to prevent connections from particular IP addresses:


  • Can I restrict what connected people are able to do?

    Yes, if you have a Professional or Enterprise subscription.

    You can register any number of users or groups (perhaps from your corporate network) with VNC Server:


    You can then grant specific permissions to each. So for example you could grant system administrators full remote access, members of the group ‘teachers’ sufficient permissions to control the remote computer but not to transfer files or print, and make members of the group ‘pupils’ view-only.

    If you have a Home subscription, all connected users have the same global permissions, though you can turn individual features off for everyone, or make all connections view-only, if you wish. It will also apply to you though!

  • Can I blank the screen of a remote computer while I’m connected to it?

    You can blank the screen of a Windows 7 computer while you’re remotely controlling it, so people in the vicinity can’t see what you’re doing:


    This is equivalent to turning the monitor of the remote computer off and not allowing it to be turned back on again until you disconnect.

    Unfortunately, you can’t yet blank the screen of any other computer, including a Windows 8 or Windows 10 computer.

  • How do I prevent the remote keyboard and mouse being used?

    You can prevent the keyboard and mouse of the remote computer being used by whoever wanders past while you're remotely connected to it:


  • How can I protect a remote computer when I’m not connected to it?

    You can configure VNC Server to automatically lock or log out from a Windows or Mac computer when you disconnect:


    Of course, you can always lock or log out during your remote control session. Just don’t power the remote computer off, or you’ll be disconnected until someone turns it on again!

  • What data does RealVNC store in the cloud?

    We never store your session data, nor VNC Server passwords. We don’t store payment or credit card information either; that’s stored on our behalf by a PCI DSS-compliant vendor (Braintree).

    We do store certain data in the following circumstances:

    • When you install VNC Connect we prompt you to enable automatic update checks and analytics.
    • If you sign in to VNC Viewer on multiple devices then we automatically sync your address book so you don’t have to recreate it each time.

    See our privacy policy for what data is collected and where it is stored.

    If you don’t want RealVNC to store any data at all then you must:

    1. Buy an Enterprise subscription
    2. Establish direct connections only
    3. Turn off update checks and analytics
    4. Use VNC Viewer without signing in to it.



Security whitepaper

A complete overview of the features, policies and controls that keep your computers and data protected wherever you are.

Download PDF
mfa resource

Multi-factor authentication

Learn how to protect both your RealVNC account and your remote computers running VNC Server with as many authentication factors as you need.

Find out more
rfb test

RFB 5 security analysis

An analysis of the security aspects of the latest version of the RFB protocol, from our in-house Security team.

Download PDF
privacy resource

RealVNC privacy policy

Our privacy policy makes it clear what data we collect, where it's stored, how it’s protected and when it’s used.

Find out more

Regulatory compliance

VNC Connect supports PCI DSS compliance

Download PDF

VNC Connect supports HIPAA compliance

Download PDF

Need more information?

If you want more details or wish to speak with a member of our Security team, let us know.

Get in touch