Malware found in Google Play Store app stories are becoming so regular you could set your watch by them. There have been a lot in recent memory, but the biggest by far has been the bulk action Google was forced to take against Chinese app developer DO Global. With apps totaling over half a billion downloads, DO Global’s ban, for a number of reasons including sharing user data with the Chinese government, sent shockwaves through the app world.
It now looks, however, like Google’s problems with apps from China are far from over as a new security report has shed light on some worrying findings. According to the report, Google has a serious problem with the Chinese-based firm Cootek, due to unauthorized adware that can render victims’ mobile phones almost completely unusable.

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Read now238 apps with over 440 million downloads between them have shipped with an aggressive form of adware
Security research firm Lookout has released details of a new study its team has performed looking into apps on the Google Play Store. The study’s findings show that a particularly nasty piece of adware called BeiTAd has been found in 238 apps on Google’s app store. 237 of the apps were published by the aforementioned Cootek.

BeiTAd is a rather invasive piece of adware as it propagates “out of app” ads. After the infected apps are downloaded, the plug-in lies dormant for up to a couple of weeks but then wakes to cause havoc on the victim’s device. Basically, out-of-app ads start popping up all over the device, not just in the infected app, including places like the lock screen. Even worse, the plugin could trigger video ads to play while the phone is in sleep mode.
In the report, Lookout researcher Kristina Balaam points out just how bad this adware is, “While out-of-app ads are not particularly novel, those served by this plugin render the phones nearly unusable. Users have reported being unable to answer calls or interact with other apps, due to the persistent and pervasive nature of the ads displayed.” In many cases, the onset of ads has been so bad that they’ve interrupted regular use of the device.

The good news is that Lookout has shared its findings with Google and the internet giant has already taken action. All of the affected apps have either been removed, or updated to new versions that don’t include the BeiTAd plugin. This means if you suspect you might have downloaded a Cootek plugin or you’ve been experiencing problems like those described above, you should update your apps immediately.
Unfortunately, due to the large number of affected apps we can’t list them all here. If, however, you want to check your apps against the list, you’ll find it here.