Communication Technologies

Security Issues with Open Networks

When you connect to an open Wi-Fi network, your data travels without encryption — meaning anyone with the right tools can potentially intercept it. Here are the key security issues to know:

• Man-in-the-middle attacks occur when a criminal secretly positions themselves between your device and the network. You think you're communicating directly with a website, but the attacker is silently reading or even altering your data as it passes through.
• Packet sniffing is where an attacker uses software to capture the raw data travelling across the network. On an open network, this data is unencrypted, so usernames, passwords, and messages can be read as plain text.
• Rogue hotspots (sometimes called evil twin attacks) involve a criminal setting up a fake Wi-Fi network with a convincing name — "Airport_Free_WiFi", for example. Unsuspecting users connect to it thinking it's legitimate, handing the attacker full visibility of their traffic.
• Unauthorised access is a broader risk — because open networks require no authentication, there is no way to control who joins. Any device on the same network could potentially attempt to access shared files or exploit vulnerabilities in other connected devices.

The underlying problem with all of these is the same: open networks have no password, so there is no encryption protecting the data in transit, and no barrier stopping malicious users from joining.