Malware can be so dangerous that they can infect, steal and even take over devices that are infected by it.
App stores are certainly the best place to download apps, but apparently Google's Play store is having a security issue making a bunch of Android malware to find their way into the store in one of the biggest outbreak to hit Google's platform.
With as many as 21.1 million infections from just one malware family. The malware has been dubbed as the "ExpensiveWall."
This ExpensiveWall malware hides inside wallpaper, video and photo editing apps.
According to researchers from Check Point, the infected app can send fraudulent premium SMS messages and charge users for fake services. ExpensiveWall infected at least 50 apps, which together were downloaded between 1 million and 4.2 million times, according to data from Google Play.
A previous sample of the malware, uncovered by McAfee, was installed millions of times too, taking the total number of victims to somewhere between 5.9 million and 21.1 million.
Google Play on its own has a built-in anti-malware protections, but those infected apps apparently got past Google's security measures because the malware was “packed” using an advanced encryption techniques to hide its malicious code, according to Check Point.
In terms of the biggest ever Android malware, Check Point researcher Daniel Padon said that ExpensiveWall was probably second only to Judy, though he couldn't put an estimate on how much the hackers have made on their fraud attemps.
Check Point first disclosed its ExpensiveWall findings to Google on August 7th.
Google removed the incriminating apps just like it was told, but apparently the hackers were able to improvise and upload more samples to Google Play, infecting 5,000 devices before being removed four days later.
A Google spokesperson said: "We've removed these apps from Play and always appreciate the research community's efforts to help keep the Android ecosystem safe."
ExpensiveWall doesn't just fraud user for money. The malware also steals data like users' locations and IP addresses. It also shows online advertisements where users were forced to click. As another money-making scheme, the hackers were at the end receiving those ad clicks payouts.
Beside ExpensiveWall and Judy, Google Play's platform has been a target by various of hackers and frauds over the years. But with this many users infected, Google still has a lot of work to do to secure its popular Android from fraudsters that exploit its openness.