Security firm AirDefense is issuing a warning against a new phishing scheme that targets WiFi networks.

The Atlant-based firm said the scam was first discovered at a wireless local area network event in the United Kingdom and was detected against last week at the Interop trade show in Las Vegas.

“The latest attack works when a hacker creates a fraudulent web site that has the look and feel of a log-in page to a WiFi network, when in reality the site is bogus,” AirDefense said in a statement. “When a user logs into the fraudulent network, as many as 45 viruses are sent to computers that accessed it. AirDefense does not believe that everyday users of public hotspots should be fearful, but executives using WiFi in airport lounges and on any business trip should take preventative steps against the newest scam:

AirDefense said the attack is “more sophisticated” than the Evil Twin attack launched in January.

To fight WiFi intrusion, AirDefense recommends the following:

1. Install personal firewall and security patches.

2. Enter passwords only into web sites that include an SSL key at bottom right.

3. Avoid hotspots where it is difficult to tell who is connected, such as at hotels and airport clubs. Use hotspots for web surfing only.

4. Turn off or remove your wireless card if you are not using the hotspot.

5. Do not use insecure applications such as e-mail or instant messaging while at hotspots.

For a free version of AirDefense’s personal firewall, see: www.airdefense.net/products/adpersonal/