Cheap Phone Has Cheap Security

Nathan Collier, a senior malware intelligence analyst with Malwarebytes Labs, has found that a low-cost Android phone made in China has two large malware files pre-installed by the manufacturer that directly affect the purchaser of the phone.

He seems particularly incensed that the phone is allowed to be a part of the US government-funded Lifeline Assistance program. The program financially assures that lower-income people are able to communicate via phone subsidies.

The actual phone that we're talking about here is sold by Virgin Mobile's Assurance Wireless as the UMX U686CL. This phone is the most budget-conscious option under their Lifeline Assistance program, and is priced at $35.

The first malware app found on the phone is called "Wireless Update". This app is the only way on the phone to update the operating system if needed. While it will indeed perform that function, Collier says that it is also capable of auto-installing apps without any user consent.

Further, he says in his blog, the malware "is actually a variant of Adups, [from] a China-based company caught collecting user data, creating backdoors for mobile devices and, yes, developing auto-installers."

Although he was unable to find any specific malware files on the phone that were loaded by the updater upon initialization, he felt that it was important to note that any of the apps that were added to the device required zero notification or permission from the user. He thinks that this opens the potential for malware to unknowingly be installed in a future update to any of the apps added by Wireless Update at any time.

So, he finds that there is a potent attack route embedded in a major functionality of the phone.

Additionally, Collier notes that the phone's Settings App (which serves as the dashboard from which settings are changed) shares characteristics in its code with two other variants of known mobile Trojan droppers.

After the library that is hidden in the Settings app is loaded into memory, it will then drop another piece of malware known as Android/Trojan.HiddenAds.

Malwarebytes Lab users have reported that a variant of HiddenAds suddenly installs on their UMX mobile device, confirming Collier's analysis.

To mitigate the problem, the user faces some real choices. If the Update app is removed, a critical operating system upgrade may be bypassed. Some users may wish to pursue this option if they think they can carry out any needed OS updates on their own.

But the Settings app must be present for the phone to function at all. Complete removal is not an option here. Collier points to another Malwarebytes blog entry on dealing with pre-installed malware for guidance.

Collier is not so sanguine about Assurance Wireless, however. He pointedly notes in the blog: "We informed Assurance Wireless of our findings and asked them point blank why a US-funded mobile carrier is selling a mobile device infected with pre-installed malware? After giving them adequate time to respond, we unfortunately never heard back."

— Larry Loeb has written for many of the last century's major "dead tree" computer magazines, having been, among other things, a consulting editor for BYTE magazine and senior editor for the launch of WebWeek.