Comms chips

WiMax's Small Steps to Security

Sprint Corp. (NYSE: S)'s decision last week to spend $3 billion on a new high-speed wireless network gear catapulted WiMax right into the public eye. But what Sprint didn't talk about -- and is less well understood -- is what security measures will protect users who move over to the broadband wireless network. (See Sprint Goes WiMax.)

Analysts, industry experts, and operators are expecting to see some of the same kinds of attacks undertaken against the older 802.11 WiFi standard used against its younger sibling. "I expect we'll see similar problems with [WiMax] as we've seen with other devices, namely weak management protocols and vulnerable applications -- embedded Web servers, unencrypted access via telnet and SNMP V1 and V2," says ex-Tipping Point security consultant Shawn Merdinger.

Security will become a bigger issue with WiMax and other high-speed wireless services, if enterprise experience with WLAN technologies is any indication. Access and authentication remain key wireless concerns for enterprise buyers and users.

There is, however, an increasing awareness that wireless's weakest link may not be in the security methods used to protect it, but rather in the insecure coding at the software driver level, which can be exploited by clever hackers.

"I don't think WiMax is any less secure than WiFi or cellular, both of which I think are secure," says Ken Dulaney, VP of mobile computing at Gartner Inc. "You will probably see some attacks, but I warn everyone who claims it's a WiMax failure to see whether the problem results from other areas," whether faulty drivers or something else, Dulaney says. WiMax and WiFi are both borne of the same orthogonal frequency-division multiplexing (OFDM) technique, he adds.

John Larson, research scientist at Sprint Labs, says gaining access to a device via faults in its drivers is one type of attack that concerns Sprint. Similar hacks at the recent Black Hat security show demonstrated how easily malicious types could gain access to an unsuspecting user's laptop using such drivers. "That's exactly what I'm thinking about," says Larson. "One of the things we really need to do is make sure we work with our vendors on that."

Waiting on Profiles
In fact, the requirements for a complete wireless security system are not even covered by the basic specification. The 802.16 standard -- and hence WiMax -- only defines the air interface and the PHY (physical) and MAC (media access control) layers. This still leaves work to be done on security and network-to-network communications. Little, if any, of this ambiguity is slowing down equipment makers. "Standards still seem to be a moving target in this area, but plenty of vendors are rolling out gear already," says security consultant Merdinger. "It should be interesting to see how well this early gear operates down the road." The IEEE standard says that data being broadcast over the airwaves must be encrypted. The fixed wireless standard 802.16d uses the Advanced Encryption Standard (AES).

Meanwhile vendors are still discussing the Extensible Authentication Protocol (EAP) methods that could be used with mobile WiMax. "It's not yet been agreed on," says Dave McGinness from the CTO organization at Sprint Nextel.

When they first find and connect to a new WiMax network, devices will send out a "manufacturer's certificate" to assure the network that the device is what it appears to be. From what Unstrung has seen and heard, vendors and operators will likely have to work together to implement more complicated certification systems for applications like e-commerce.

"We feel like we have a really good toolkit, but it's the implementation of that toolkit that counts," says McGinness.

Indeed, this has been a constant issue with WiMax, simply because the standard offers a smorgasbord of options within the specification that could be implemented. This has already led to the suggestion of interoperability problems between the fixed and mobile specifications. (See WiMax: A Spec Divided.) Since official Mobile WiMax products are not even on the market yet it's hard to gauge exactly the level of concern about WiMax security. The Sprint WiMax network will start to be switched at the end of 2007 but the big push will come in 2008.

— Dan Jones, Site Editor, Unstrung

M Finneran 12/5/2012 | 3:43:22 AM
re: WiMax's Small Steps to Security I really can't see any reason to expect that WiMAX will be less secure than cellular data services. Wi-Fi security was a mess because the tools were poor (WEP), and the networks were installed by amateurs. Carriers like Sprint know what has to be done to secure a network, and those "driver flaw" issues that were identified at Black Hat have largely been dubunked.

By the way, referencing AES as the encryption standard 802.16d (i.e. 802.16-2004) and EAP being considered for 802.16e (i.e. 802.16-2005) is a bit of apples-and-oranges. AES is an encryption standard, and EAP is a framework for authentication.
joset01 12/5/2012 | 3:43:22 AM
re: WiMax's Small Steps to Security re: AES/EAP

As far as I know AES will be part of the final mobile WiMAX profiles as well (if you know different perhaps you could enlighten me further), possibly along with possibly along with other encryption specs. I mentioned the debate over which authentication mechanisms to illustrate how fluid the whole security situation around WiMAX still seems to be.

The specific Mac Hack at Black Hat may have been debunked but I hope that doesn't mean that people stop taking these driver-level hacks seriously. The Sprint people reitarated their concerns on this point several times -- they're taking it seriously.

-- DJ
meshsecurity 12/5/2012 | 3:43:17 AM
re: WiMax's Small Steps to Security Hint:

Think about the vulnerabilities/exploits that are prevalent in the 3G world today...they exist.

turbinado 12/5/2012 | 3:43:14 AM
re: WiMax's Small Steps to Security Another point worth mentioning is KT's decision decision to use the SIM card combined with EAP functionality for Wibro authentication. KT can also leverage the secure SIM platform to roam onto KTF's 3G network and serve as a platform for other secure applications.

meshsecurity 12/5/2012 | 3:43:04 AM
re: WiMax's Small Steps to Security EAP-SIM is old school....


Even they got it down about 4+ years ago....

IPobserver 12/5/2012 | 3:42:12 AM
re: WiMax's Small Steps to Security Think about the vulnerabilities/exploits that are prevalent in the 3G world today...they exist.

Yes, but for the vast majority this really isnGt an everyday problem.

Perhaps IGm being na+ve, but I feel pretty comfortable with 3G network security G and with HSPA you can run a VPN as well.

More worrying are the potentially dodgy unsigned apps you can download to Symbian, etc.
meshsecurity 12/5/2012 | 3:42:11 AM
re: WiMax's Small Steps to Security Symbian to IE exploit?

IPobserver 12/5/2012 | 3:42:11 AM
re: WiMax's Small Steps to Security I donGt know about specific exploits and such (or really understand much of this G IGm too dumb), but what IGve picked up from asking experts:

* The 3G network side has vulnerabilities (around GTP and PDP hijacks, etc), but this can be dealt with and wonGt affect end-users much. Only operators and very security-sensitive companies need worry about this.

* Inside the tunnel attacks are a major concern for everyone. Apparently, simulations show a virus loose in the handset population (i.e. that can replicate) could potentially bring down a cell network in 8 minutes!

* Attacks on the handset OS. I think Series 60 v3 (Symbian) is trying to shift to signed apps to try and mitigate this. DonGt know about Windows Mobile or Linux. Seems like a huge worry.

* Vulnerabilities from connecting your (compromised) phone to your PC. The phone becomes a Trojan horse and compromises the PC. Again, this seems like a major worry.

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