US security firm Zscaler has discovered a malicious Android app that held people to ransom.
“Adult Player” appeared to offer porn, but secretly took pictures of users with the phone’s front-facing camera. It then locked the user’s device and displayed a demand for $500 (£330) which was difficult to bypass.
Apps which demand money from people with a threat to release private information, or wipe a device, are known as ransomware.
In August, Intel Security said examples of ransomware had increased 127% since 2014 – primarily affecting desktop computers and laptops.
“One of the reasons for the increase is that it’s very easy to make,” said Raj Samani, chief technology officer for Intel Security in Europe.
“There are people you can pay to do the work for you, and it pays really well. One group we tracked made more than $75,000 in 10 weeks.
 “Apps like this rely on the embarrassment factor. If you don’t pay, your reputation is on the line.”
Adult Player was the second example of pornography-focused ransomware discovered by Zscaler.
The app was not available from vetted storefronts such as Google Play, but could be installed directly from a webpage.
Zscaler said the app’s ransom message kept the phone’s screen switched on at all times, and reappeared if the handset was restarted.
“Ransomware is more prevalent on computers than phones, but this could be the start of a trend,” said Mr Samani.
“You can stay safe with some basic common sense. Some ransomware threatens to delete your photos, videos and documents so back up your data. Then if you are targeted you can wipe your system and start over.
“Only download apps from the proper Google Play store. And if you receive an app download link in an email, don’t click it.”
Zscaler said anybody that had downloaded Adult Player should reboot their handset into “safe mode”. The exact method varies between handset manufacturers.
- Boot device into safe mode. Safe mode boots the device with default settings without running third party apps.
- Uninstalling ransomware from device requires you to first remove administrator privilege. To do the same, go to Settings –> Security –> Device Administrator and select ransomware app, then deactivate.
- Once this is done, you can go to Settings –> Apps –> Uninstall ransomware app.
Safe mode loads the operating system without running any third-party apps, allowing people to delete malicious software.
