Is It Safe to Use an Open Wireless Network?

Be aware of security concerns and the need for permission

If your wireless service is down and you need an internet connection, you may be tempted to connect to any open, unsecured wireless network your wireless access point finds. Before you connect, however, you should know the risks of using open Wi-Fi networks.

Free WiFi sign.
 John Moore/Getty Images

What Is Open Wi-Fi?

It's not safe to connect to an unknown open wireless network, particularly when transferring sensitive data, such as an online banking password. All information sent over an unsecured wireless network — one that doesn't require a Wi-Fi Protected Access (WPA) or WPA2 security code — is sent in plain text for anyone to intercept. Connecting to an open network potentially opens your device to anyone else on that same wireless network.

The Risks of Using Unsecured Wi-Fi Networks

When signing in to a website or using an application that sends data in clear text over a network, anyone so inclined can easily capture that information. Your email address and password, for example, if not transferred securely, are all a malicious hacker needs to access your email account and any confidential or personal information in it without your knowledge. Similarly, hackers can capture any instant messaging or unencrypted website traffic.

If your computer isn't behind a firewall or isn't configured correctly and file sharing is enabled on it, a hacker can access the computer's hard drive over the network to get at confidential or sensitive data or even launch spam and virus attacks.

How Easy Is It to Hack a Wireless Network?

The tools needed to learn about a wireless network, capture (sniff) the data transmitted over it, crack the Wired Equivalent Privacy (WEP) security key, and decrypt and view data on networked devices can be purchased for about $50.

Is It Legal to Use Someone Else's Open Wireless Network?

In addition to the security issues for your devices and data, using a wireless network that someone else maintains and pays for may raise legal issues. In the past, several cases of unauthorized access to Wi-Fi computer networks have resulted in fines or even felony charges.

Public Wi-Fi hotspots that are set up specifically for guests to use, such as at a coffee shop, are fine. Be sure to pay attention to security, however: Wi-Fi hotspots are typically open, unsecured wireless networks.

So, if you use your neighbor's Wi-Fi connection, ask for permission first.

How to Safely Use Public Wi-Fi

There are a few things you can do to protect your privacy and data when using an open Wi-Fi network.

  • Use a VPN. A virtual private network (VPN) creates a secure tunnel over a public network. If your company provides VPN access, use the VPN connection to access corporate resources and create secure browsing sessions.
  • Don't allow automatic connections to non-preferred networks. On your device, disable the setting to automatically connect to non-preferred networks. If this setting is enabled, your computer or mobile device automatically connect to any available network, including rogue or bogus Wi-Fi networks designed to lure unsuspecting data victims.
  • Enable or install a Firewall. A firewall is the first line of defense for your computer (or network, when the firewall is installed as a hardware device). Both Windows and macOS operating systems have built-in firewalls that prevent unauthorized access; you can also use a third-party program.
  • Turn off file sharing. Before you connect to a public Wi-Fi hotspot, disable file and printer sharing so that other hotspot users don't have access to your shared files.
  • Only log on to secure websites. Make sure your browsing session is encrypted and secure. The address bar should show a URL that begins with HTTPS (encrypted) rather than HTTP (not encrypted). You may also see a padlock in the address bar.
  • Don't conduct financial transactions. Avoid using a public hotspot for banking, online shopping, or any scenario involving sensitive information.