In only one update, the popular barcode scanner app on Google Play has been transformed into malware and has been able to hijack up to 10 million devices.
Barcode Scanner by Lavabird Ltd. was an Android app available in the official repository of the Google app for years. The app, which counts more than 10 million installs, provided the QR code reader and the barcode generator, a useful mobile device resource.
The mobile app has been seen as a legitimate, reliable, multi-user software that has installed the app over the years without any problems – until recently.
According to Malwarebyte, users have recently started complaining about ads that appear unexpectedly on their Android devices. It is often the case that unwanted programs, ads, and malicious releases are linked to the installation of a new app, but in this case, users have reported that they have not installed anything recently.
After the investigation, researchers identified the Barcode Scanner as the major incident.
A software update released approximately December 4, 2020, changed app functions to compress advertising without warning. While many developers are placing ads in their software to offer free versions – and paid apps do not show ads – in recent years, switching apps from one-to-one adware apps overnight has become commonplace.
“Ad SDKs can come from a variety of third-party companies and provide a source of revenue for the app developer. It’s a win-win situation for everyone,” said Malwarebytes. “Users get a free app, while app developers and SDK ad developers get paid. But from time to time, the SDK ad company can change something in its end and ads can start to get aggressive.”
In some cases, ‘aggressive’ advertising methods may be the fault of third-party SDKs – but this is not the case with the Barcode Scanner. Instead, researchers say the malicious code was suppressed in the December review and was too hidden to avoid detection.
The update was re-signed with the same security certificate used in previous, clean versions of the Android app.
Malwarebyte has reported its findings to Google, and the tech giant has now released an app on Google Play. However, this does not mean that the app will disappear on the affected devices, so users need to manually uninstall the bad app.
Converting clean SDKs into bad packages is the only method used to avoid Google Play protection, with time testing, longer display times, loosening of open source libraries used by the app, and powerful uploads identified as invaders to compromise your mobile device.
Another exciting feature, seen by Trend Micro, is the launch of a motion sensor check. By 2019, Android apps have been found to contain Anubis Trojan bank, which will only work if they remove their handset.