Trend Micro researchers at Black Hat Asia are warning that millions of Android devices worldwide come pre-infected with malicious firmware before the devices leave their factories. “This hardware is mainly cheapo Android mobile devices, though smartwatches, TVs, and other things are caught up in it,” reports The Register. From the report: This insertion of malware began as the price of mobile phone firmware dropped, we’re told. Competition between firmware distributors became so furious that eventually the providers could not charge money for their product. “But of course there’s no free stuff,” said [Trend Micro researcher Fyodor Yarochkin], who explained that, as a result of this cut-throat situation, firmware started to come with an undesirable feature — silent plugins. The team analyzed dozens of firmware images looking for malicious software. They found over 80 different plugins, although many of those were not widely distributed. The plugins that were the most impactful were those that had a business model built around them, were sold on the underground, and marketed in the open on places like Facebook, blogs, and YouTube.
The objective of the malware is to steal info or make money from information collected or delivered. The malware turns the devices into proxies which are used to steal and sell SMS messages, take over social media and online messaging accounts, and used as monetization opportunities via adverts and click fraud. One type of plugin, proxy plugins, allow the criminal to rent out devices for up to around five minutes at a time. For example, those renting the control of the device could acquire data on keystrokes, geographical location, IP address and more. “The user of the proxy will be able to use someone else’s phone for a period of 1200 seconds as an exit node,” said Yarochkin. He also said the team found a Facebook cookie plugin that was used to harvest activity from the Facebook app.
Through telemetry data, the researchers estimated that at least millions of infected devices exist globally, but are centralized in Southeast Asia and Eastern Europe. A statistic self-reported by the criminals themselves, said the researchers, was around 8.9 million. As for where the threats are coming from, the duo wouldn’t say specifically, although the word “China” showed up multiple times in the presentation, including in an origin story related to the development of the dodgy firmware. Yarochkin said the audience should consider where most of the world’s OEMs are located and make their own deductions.
The team confirmed the malware was found in the phones of at least 10 vendors, but that there was possibly around 40 more affected. For those seeking to avoid infected mobile phones, they could go some way of protecting themselves by going high end. That is to say, you’ll find this sort of bad firmware in the cheaper end of the Android ecosystem, and sticking to bigger brands is a good idea though not necessarily a guarantee of safety. “Big brands like Samsung, like Google took care of their supply chain security relatively well, but for threat actors, this is still a very lucrative market,” said Yarochkin.
Read more of this story at Slashdot.
