FakeID and MasterKey Still Pose Risks for Android

Google patched both flaws, but in some cases, users have not updated their devices and, in others, the device vendor may not have made a patch available.

Android security

Jeff Forristal has been busy the last few years discovering and reporting Android vulnerabilities. Forristal, CTO of mobile security vendor Bluebox Security, revealed the Android Master Key vulnerability at the Black Hack 2013 conference and the FakeID vulnerability in 2014.

The two security flaws could have potentially enabled malicious apps to be installed on user devices. Although Google has patched both flaws, there are still users that are at risk from the vulnerabilities for a number of reasons. In some cases, they have not updated their devices. In others, the device vendor may not necessarily have ever made a patch available.

Bluebox has had a security scanner available in Google Play since 2013 that now scans for both Master Key and FakeID vulnerabilities. Even now, more than 18 months after the flaw was patched in the upstream Google Android code, the scanner still finds users at risk from MasterKey, Forristal said.

"You cannot depend on the Android OS version as being an indicator about whether or not you are patched, and that's the same for both MasterKey and FakeID," Forristal told eWEEK.

Some Android device vendors have made patches available for the older Android 4.2 release, while some vendors have not made patches available, he explained. (The latest version of Android is now the 4.4 KitKat release.)

"Ultimately, as bugs come out, it is cheaper and easier for some manufacturers to back-port the patch for a security issue into an older version of Android that a device is using, rather than trying to update the device to a brand new Android version," Forristal said. "What gets patched and what doesn't get patched is generally tied to vendor good will, and the support time span for a given device."

The challenge of Google Android device patching is nontrivial. Google Play recognizes more than 7,300 devices, each with its own patching history, Forristal said.

Some vendors are more active than others in providing timely updates for Android security issues, Forristal said. Motorola has a quick turnaround for Android patches, and when it comes to Samsung, currently supported devices tend to get proper updates as well, he said.

"We have some evidence that Google has been putting pressure on Android device partners to make sure that security vulnerability updates happen at a healthy pace that is measured in a 90- to 120-day time frame," Forristal said.

The bigger challenge, however, likely is around the length of time a vendor will support a given device and how that maps to user ownership of the device. With carrier-subsidized smartphones, a user could get a phone from a carrier and be locked into a two-year contract.

However, most vendors typically only have a two-year support lifecycle for devices in terms of software patches. As such, Forristal noted that if the user buys a phone model that has already been out in the market for a year and a half, that phone might only have six months left of its lifespan for software patch updates.

"It's a really interesting dynamic of how carrier subsidies can lock consumers into a device, that may be hitting its end of life for patches before the contract is over," Forristal said.

In an ideal scenario, vendors would be able to support phone models for up to four years, with carriers selling any given device for only two years; however, that's a scenario that is unlikely to play out, since it's complicated and difficult to support any given phone model for four years, Forristal said.

Sean Michael Kerner is a senior editor at eWEEK and InternetNews.com. Follow him on Twitter @TechJournalist.

Sean Michael Kerner

Sean Michael Kerner

Sean Michael Kerner is an Internet consultant, strategist, and contributor to several leading IT business web sites.