Apple’s security concessions in corporate devices may have created a loophole in an otherwise secure system, according to new research from Check Point Software Technologies, a company that sells internet security hardware and software. When successful, this "SideStepper" attack gives perpetrators access to victims’ devices, including their data, as well as the power to install malicious apps. The new attack takes advantage of less rigorous software controls for corporate device users, particularly those who use Mobile Device Management solutions (or MDMs) to get apps delivered to their phones.
The majority of device owners aren't susceptible to the attack because they don't use MDMs. Even those who do, have to fall for a phishing text message, and then ignore security warnings about the malicious download. Though the attack is hard to pull off, SideStepper shows how common corporate practices can open the door to otherwise impossible iOS attacks. Successful attackers gain unprecedented powers, allowing them to masquerade as the device's manager and control it remotely.
The attack exploits less rigorous software controls for corporate device users
Corporate IT teams often use MDMs to deliver professional apps to their employees automatically and without the hassle of having them approve what goes on their devices. These apps are typically private and not listed in the App Store. They're not reviewed, approved, or hosted by Apple. Savvy SideStepper attackers harness this corporate loophole in order to install their own malicious apps and essentially conduct a man-in-the-middle attack.
The device receives a malicious app
Check Point details the process in its white paper published this morning. Once the malicious configuration profile is installed, it automatically sets up a remote enterprise app server that enables a man-in-the-middle attack. From then on, whenever the user’s legitimate MDM server sends a command, the compromised device instead calls back to the attacker’s malicious server. The device will receive a malicious app, as opposed to the real update it initially sought, and victims will have no idea.
An Apple spokesperson commented to The Verge: "This is a clear example of a phishing attack that attempts to trick the user into installing a configuration profile and then installing an app. This is not an iOS vulnerability. We've built safeguards into iOS to help warn users of potentially harmful content like this. We also encourage our customers to download from only a trusted source like the App Store and to pay attention to the warnings that we’ve put in place before they choose to download and install untrusted content."
It isn’t clear how many devices are susceptible to this attack. Check Point doesn't offer an estimate. Forrester Research reported in 2014 that Apple products accounted for eight percent of global business and government spending in 2009, and at the time, it expected that figure to reach 11 percent in 2015. The firm hasn’t updated its numbers, and it isn't clear how many of those devices are attached to MDMs.
SideStepper isn't the first attack to prey on company devices. In 2014, Palo Alto Networks discovered a malware called Wirelurker. That malware also exploited companies' ability to automatically install apps without Apple's intense App Store approval process. That malware primarily affected Chinese users and was dismantled prior to wider infection. In this case, Apple hasn't yet addressed the loophole, and given that SideStepper isn't malware, the company can't simply patch the security problem. Addressing this attack would mean rethinking how it designs systems for corporate clients.