Via numerous e-commerce websites as well as marketplaces like eBay and AliExpress you can easily find smartphones that are significantly cheaper than what you'd pay for a phone with similar specifications from a well-known brand. A lot of Chinese brands have captured a widely following as they deliver a very good price/performance ratio, but unfortunately not all of them can be trusted.
A new report by anti-virus firm Doctor Web claims they discovered 26 cheap phones that come pre-loaded with a downloader named Android.DownLoader.473.origin. This piece of software can download benign applications but also malicious and unwanted ones, including adware. The company also discovered another preinstalled downloader dubbed Android.Sprovider.7, this one has the ability to make phone calls to certain numbers and to show ads on top of apps.
"It is known that cybercriminals generate their income by increasing application download statistics and by distributing advertising software," the security researchers wrote. "Therefore, Android.DownLoader.473.origin and Android.Sprovider.7 were incorporated into Android firmware because dishonest outsources who took part in creation of Android system images decided to make money on users."
Here's an overview of affected smartphones. Probably the biggest surprise are the two Lenovo devices on the list, these contained the Android.Sprovider.7 trojan. A quick Google search of various models mostly turned up Russian sites so the odds of coming across these phones in other geographies are pretty low.