Five WiFi VOIP Security Issues

As enterprise deployments of WiFi VOIP systems reach the staging point, security will be a key concern for enterprise users.

Shawn Merdinger, an independent security consultant based in Austin, Texas, has worked with Cisco Systems Inc. (Nasdaq: CSCO) and 3Com Corp. (Nasdaq: COMS)/Tipping Point. He's tested around a dozen WiFi VOIP handsets and deskphones and says that security problems range from potential denial-of-service attacks to more serious issues that allow "deep access" to the device that lets a remote attacker read sensitive information on the phone.

You can see his postings on many of the devices tested, along with some workarounds here. In the wake of Merdinger's findings, Cisco Systems Inc. (Nasdaq: CSCO), Hitachi Ltd. (NYSE: HIT; Paris: PHA), and UTStarcom Inc. (Nasdaq: UTSI) have issued firmware upgrades for the devices in question. (See WiFi VOIP: How Safe?.)

Such threats are inevitable. So it's up to vendors to forestall them, according to analyst Paul Stamp, of Forrester Research Inc.

"It's security 101. If we see practices like this continue as these devices get more popular then the manufacturers will only have themselves to blame when there's a widespread attack," he notes.

Still there are steps users can take to protect themselves. Here's a Top 5 list of enterprise WiFi VOIP security issues, and some ways to guard against them:

Widespread deployment equals a security headache:
Because of the "ubiquity of deployment" in many enterprises, attacks can spread quickly and be targeted to take down multiple devices at once. IT managers should stay up to the minute with phone upgrades, and consider running phones over a separate physical or virtual LAN as a defense against these attacks.

Many points of attack:
As the phones get more sophisicated, so could the points of entry for malicious attacks increase. Bluetooth, email, client Web browsers, SMS, WiFi, media players, and image viewers could open back doors for hackers. Though users can use open-source and commercial tools to continually test their phones and networks, they'll ultimately have to rely on vendors to do proactive testing on these devices.

"Some vendors may engage in this testing while the majority will not," warns Merdinger.

Targeting phones in public environments:
For example, a Bluetooth scanner could be hidden at the entrance to a major airport or train station and be used to grab user data. It may be best to keep Bluetooth and other wireless features swicthed off when not needed.

Rogue again:
Meanwhile, at the office and on the road, users and IT departments will have to keep their guard up and scan for rogue access points. Hackers will set up access points to specifically target WiFi phones in the corporate space as well as at hotels, conferences, and other places business people like to congregate. Good device authentication and encryption can help provide protection here.

Targeted attacks:
Targeted attacks on specific voice-over-wireless networks could also be an issue, albeit one that the victims may try to downplay. "There will be targeted attacks on VoIP networks [from hackers or competitors] that will be kept quiet if there is no legal requirement for disclosure or obvious public knowledge," Merdinger says.

Users, however, shouldn't get in a snit about VOIP calls that are often unencrypted and therefore easier to listen in on. Unless attackers are targeting a specific user, it is much simpler to find useful information sent by the user or held on the phone than to listen in on calls, even if you're the NSA.

"Most attackers are going to go after text information -- much easier to parse for the juicy information," says Merdinger.

— Dan Jones, Site Editor, Unstrung