By Ran Schwartz
Over recent years, there has been a lot of activity on Google’s part to improve the security of its Google Play app store. Why? Because millions of users have inadvertently downloaded thousands of malicious applications from the store which have compromised their data including SMS, credentials, photos, calendars appointments, and emails. For example, in March 2019, the ‘SimBad’ adware was found in over 200 apps on the store, with a combined download count of nearly 150 million.
Since the formal formation of the alliance, over 5.2 million installations of malicious apps took place, spanning dozens of different campaigns of four different types of malware.
These malware families have a range of capabilities: from the ability to steal all information from the device, to taking over the device by popping up advertisements or overlay windows as a form of a phishing attack. These apps also use a variety of techniques to avoid detection by the alliance’s security teams, including code obfuscation and delayed downloads of malicious payloads.
One of these campaigns has been uncovered by Check Point researchers. The Haken malware family was installed on over 50,000 Android devices by eight different malicious apps which all appeared to be benign. The apps were mostly camera utilities and children’s games: the apps were Kids Colouring, Compass, QR code, Fruits colouring book, soccer colouring book, fruit jump tower, ball number shooter & Inongdan.
The malware is classified as a “clicker” because of its ability to take control of the user device and click on anything that may appear on the device’s screen. It is important to note that malware can access any type of data, so anything visible on-screen is fair game (Hello, work emails!), and any locally stored data (Hi there, work conversations over a messaging app!).
The impact on users is two-fold: it can sign them up for premium subscription services without the user realising, earning money illegally for the people behind the app. It could also exfiltrate sensitive data from the user’s device. The good news is, these rogue applications have all been removed from Google Play.
But this does highlight that despite ongoing efforts to secure the Google Play Store against malicious apps, completely eliminating the risk of users getting a malicious download from the store is not going to happen quickly. There are nearly 3 million apps available from the store, with hundreds of new apps being uploaded daily – which makes it difficult to check every single app is safe.
Some app developers have devised ingenious methods to conceal their apps’ true intent from Google’s scrutiny. Coupled with a fragmented Android ecosystem, in which a large number of device manufacturers infrequently offer critical OS updates, users cannot rely on Google Play’s security measures alone to ensure their devices are protected.
They need to deploy security software to ward off malware and other threats, and protect the corporate and personal data on those devices. The security solution has to truly understand malicious behaviour which means it must use numerous advanced techniques that go beyond just signatures or machine-learning based on static indicators.
If you suspect you may have one of these infected apps on your device, here’s what you should do:
- Uninstall the infected application from the device
- Check your mobile and credit-card bills to see if you have been signed up for any subscriptions and unsubscribe if possible
- Install a security solution to prevent future infections
(Disclaimer: The author of this article is a Product Manager, Threat Prevention at Check Point Software Technologies and the views expressed here are the author’s own)
