Malicious cryptocurrency miners shift focus to Google Play

Cryptocurrency miners are spreading beyond computer operating systems and on to Android applications through Google Play.

The miners have popped up in applications that use JavaScript loading and native code injection to avoid detection on Google Play, TrendLabs researchers Jason Vu, Veo Zhang and Seven Shen have found.

The two cryptocurrency miners have been dubbed 'ANDROIDOS_JSMINER and ANDROIDOS_CPUMINER.

So far JSMINER has appeared in two apps: Recitiamo Santo Rosario free, a prayer app, and SafetyNet Wireless app, which apparently provides discounts.

The researchers say it is able to load CoinHive's JavaScript library code and start mining with their own site key.

They will also cause high CPU usage in the device while they are mining.

CPUMINER was spotted in at least 25 legitimate versions of apps which were hijacked to include mining libraries. The apps are then redeployed across Google Play as new apps.

One such app includes a supposed car wallpaper app called 'Car Wallpaper HD: Mercedes, Ferrari, bmw and audi'.

Researchers say it uses a modified version of cpuminer library and is also added to legitimate applications.

They suspect the criminal behind the attacks is mining different cryptocurrencies, however they are not doing do well; having netted just over US$170. Total profits, however, are not known.

"These threats highlight how even mobile devices can be used for cryptocurrency mining activities, even if, in practice, the effort results in an insignificant amount of profit. Users should take note of any performance degradation on their devices after installing an app," the researchers state.

TrendLabs researchers contacted Google, which then removed the apps from Google Play.

Cryptocurrency mining on Android devices is not new: the ANDROIDOS_KAGECOIN malware hit Google Play in 2014. It was also able to mine cryptocurrency.

The CoinHive malware has been popular this year; which was hijacked by cybercriminals to mine cryptocurrency.

It caused significant CPU usage on victims' machines – as much as 100% CPU, according to Trustwave researchers.

The CPU spike could account for as much as $14 per month to a power bill if the machine was not turned off at any time.

Because cybercriminals are exploiting servers and visitors to mine cryptocurrencies for their own means, ultimately end users are the losers.