If you’re settling down with a latte at the local coffee shop or waiting for your car to be repaired at the dealership, you might be tempted to use the free WiFi that these businesses often provide. It’s convenient to be able to use the internet while you’re waiting, but that convenience comes at the expense of security. And let’s face it, our entire *lives* are online these days, so keeping your personal information protected is important!
Hackers are all too eager to find an easy target. They can connect to unprotected or poorly-configured computers and silently listen to everything you do, including knowing which websites you’re visiting. But with a few minutes’ work, you can really bolster your security, and it’s easy.
These tips are all free, and make use of software built in to Mac OS X. Specific directions here are for Apple’s latest version of OS X, named “10.7″ or “Lion”. These tips are great for any time you’re using a network you don’t control.
First, some general security tips:
- Just because you use a password to get on the WiFi network, doesn’t mean it’s secure!
- Just because you click-through an agreement on a web page in order to use the WiFi network, doesn’t mean it’s secure, either!
- Watch out for “evil twin” WiFi networks. The bad guys create legitimate-sounding WiFi networks with names like “Free Public WiFi” or “Starbucks WiFi”. If you’re in doubt, ask an employee what the name of their WiFi network is.
- Don’t do any online banking or online shopping or *anything* that could expose passwords or financial information.
If you can, use versions of websites that support “HTTPS” connections. Those are secure connections that scramble any information you provide so that it can’t be read in transit. HTTPS also verifies that what you typed is what the website sees at their end, and verifies that the server is who it claims to be. Look for a padlock symbol on your web browser, a green address bar, or simply a web address that starts with ‘https://’. Remember, it’s the ‘s’ at the end of ‘https’ that makes all the difference. (BONUS TIP: If you’re a FireFox user, get the ‘HTTPS-Everywhere’ plugin. It will intercept your attempts to visit websites and automatically redirect you to a secure version if one is available.)
Now, for my Mac-specific recommendations:
Put your shields up
You can tell your computer to reject any attempts the bad guys might make by turning on the Firewall feature.
How to do it:
1. Click the Apple Menu in he upper left corner of the screen.
2. Choose “System Preferences” from the menu.
3. In the System Preferences window, click the “Security and Privacy” icon.
4. Click the “Firewall” tab.
5. Click the Start button to turn the firewall on. (You /may/ have to click the padlock in the bottom-left corner of the window and supply a password to make the Start button clickable.)
Turning on the Firewall is as easy as clicking the 'Start' button.
From now on, you’ll be notified whenever a program on your Mac wants to make or receive a connection from the network.
If you want to go even further, click the Advanced button, and in the subsequent window, check the boxes for “Block all incoming connections” and “Enable Stealth Mode”. With these settings enabled, your Mac becomes essentially invisible on the network.
Close the doors
Another useful step is to tell your computer to stop allowing connections for built-in services like file sharing and remote access.
How to do it:
- Click the Apple Menu in he upper left corner of the screen.
- Choose “System Preferences” from the menu.
- In the System Preferences window, click the “Sharing” icon.
- See all those checkboxes? Uncheck each of them. Close the window when you’re done. (Just like earlier, you may have to click the padlock in the bottom-left corner of the window and supply a password to make the checkboxes clickable.)
Uncheck these boxes to increase your security.
These two things by themselves make you much safer when using an un-trusted wireless network. Now, these suggestions aren’t the kind of thing you’ll need to use every day. They’re temporary settings for heightened security. Remember, you don’t run the WiFi network, and you have no idea who else is on the network with you. Once you get back home, feel free to turn your Firewall off (if you like) and re-enable the sharing services.
