Cellular Security Called Into Question. Again.

Worries about spectrum scarcity have prompted telecommunications providers to provide their subscribers with femotocells, which are small and low-powered cellular base stations. Often, these stations are linked into subscribers’ existing 802.11 wireless or wired networks, and are used to relieve stress placed upon commercial cellular towers whilst simultaneously expanding cellular coverage. Questions have recently been raised about the security of those low-powered stations:

Ritter and his colleague, Doug DePerry, demonstrated for Reuters how they can eavesdrop on text messages, photos and phone calls made with an Android phone and an iPhone by using a Verizon femtocell that they had previously hacked.

They said that with a little more work, they could have weaponized it for stealth attacks by packaging all equipment needed for a surveillance operation into a backpack that could be dropped near a target they wanted to monitor.

While Verizon has issued a patch for its femtocells, there isn’t any reason why additional vulnerabilities won’t be found. By placing the stations in the hands of end-users, as opposed to retaining control over commercially deployed cellular towers, third-party security researchers and attackers can persistenty test the cells until flaws are found. The consequence of this deployment strategy is that attackers will continue to find vulnerabilities to (further) weaken the security associated with cellular communications. Unfortunately, countering attackers will significantly depend on security researchers finding the same exploit(s) and reporting it/them to the affected companies. The likelihood of security researchers and attackers finding and exploiting the same flaws diminishes as more and more vulnerabilities are found in these devices.

In countries such as Canada, for researchers to conduct their research they must often first receive permission from the companies selling the femtocells: if there are any ‘digital locks’ around the technology, then researchers cannot legally investigate the code without prior corporate approval. Such restrictions don’t mean that researchers won’t conduct research, but do mean that researchers’ discoveries will go unreported and thus unpatched. As a result, consumers will largely remain reliant on the companies responsible for the security deficits in the first place to identify and correct those deficits, but absent public pressure that results from researchers disclosing vulnerabilities.

In light of the high economic costs of such identification and patching processes, I’m less than confident that femtocell providers are going to be investing oodles of cash just to potentially as opposed to necessarily identify and fix vulnerabilities. The net effect is that, at least in Canada, telecommunications providers can be assured that the public will remain relatively unconcerned about the security of providers’ products: security perceptions will be managed by preventing consumers from learning about prospective harms associated with telecommunications equipment. I guess this is just another area of research where Canadians will have to point to the US and say, “The same thing is likely happening here. But we’ll never know for sure.”