Following a January report on malware found pre-installed on smartphones sold in the United States to budget-conscious users, Malwarebytes has discovered another mobile device riddled with malware from the get-go.
In January, the security firm reported that the UMX U686CL phone, sold as part of the government-funded Lifeline Assistance program by Virgin Mobile, a subsidiary of Sprint, was being shipped to users with two malicious programs pre-installed: a Wireless Update application and a Settings app.
Within a month, UMX (Unimax) Communications delivered a software update to the device to completely remove the malware, although it told the security firm that the update was meant to, in fact, correct a vulnerability.
Now, Malwarebytes’s Nathan Collier says that another phone model provided through the Lifeline Assistance program was found to include pre-installed malware: the ANS (American Network Solutions) UL40 running Android 7.1.1.
While it’s uncertain whether the device is currently available through Assurance Wireless by Virgin Mobile, its user manual is listed on the carrier’s website, suggesting that it might still be available to Assurance Wireless customers.
The same as the UMX U686CL, the ANS UL40 features infected Settings and Wireless Update apps right from the start, although they were found plagued with different malware variants. The Settings app would drop Android/Trojan.Downloader.Wotby.SEK, while Wireless Update would fetch three variants of Android/PUP.Riskware.Autoins.Fota (which in turn installed variants of HiddenAds adware).
“WirelessUpdate is categized as a Potentially Unwanted Program (PUP) riskware auto-installer that has the ability to auto-install apps without user consent or knowledge. It also functions as the mobile device’s main source of updating security patches, OS updates, etc,” Collier notes.
Digging deeper, the security researcher discovered that the digital certificate for the Settings app on ANS UL40 is tied to TeleEpoch Ltd, the company that registered the brand “UMX” in the United States.
“Let’s review. We have a Settings app found on an ANS UL40 with a digital certificate signed by a company that is a registered brand of UMX. For the scoreboard, that’s two different Settings apps with two different malware variants on two different phone manufactures & models that appear to all tie back to TeleEpoch Ltd. Additionally, thus far the only two brands found to have preinstalled malware in the Settings app via the Lifeline Assistance program are ANS and UMX,” Collier notes.
Further research revealed that the ANS L51 was yet another ANS device delivered with pre-installed malware, and that it had the same malware variants identified on the UMX U683CL.
Malwarebytes believes that ANS will remove the malware from the flagged devices sooner rather than later, just as UMX did, but also presents a series of steps that users can take to ensure that HiddenAds does not re-infect their phones.
“There are tradeoffs when choosing a budget mobile device. Some expected tradeoffs are performance, battery life, storage size, screen quality, and list of other things in order to make a mobile device light on the wallet. However, budget should never mean compromising one’s safety with pre-installed malware. Period,” Collier concludes.