A widespread piece of ransomware that poses as a porn app for Android has been updated to conform with Google’s Material Design with the aim of boosting payments from victims.
Google launched its modern, flatter-looking Material Design language with Android 5.0 last year to improve how users interacted and experienced apps on Android.
Now the makers of a ransomware Trojan posing as a porn app, PornDroid, are attempting to use Google’s design scheme to add legitimacy to a bogus threat from the FBI. The goal is to improve the odds of victims paying up when presented a fine for alleged illegal internet activity.
The newly designed extortion screen, labeled by Symantec Android.Lockdroid.E, will offer victims easy-to-use swipe actions that show off to the victim what the malware has snapped and the evidence a victim might think will be used against them.
“The authors of Android.Lockdroid.E implemented Material Design to create a lockscreen with a cleaner, more professional-looking UI,” Symantec noted.
“The malware also used this design language to display the personal data that it gathers through an easy-to-access menu. These elements help the ransomware intimidate the victim into making the payment.”
Not much about what the malware captures stands out from other lockscreen ransomware though Material Design appears to have prompted a change in tactics in that it now presents details of device logs purportedly captured by authorities.
“Other ransomware families have been observed gathering the logs of SMS activity, call records, and browser history in the past. However we haven’t seen ransomware threats that make these logs more accessible to the victim through Material Design before,” Symantec noted.
The trojan app is well-known among malware researchers. Security firm ESET detailed PornDroid’s ransomware features last month, noting a shift in focus from Russian and Ukrainian victims to US targets.
According to ESET, to avoid payment, victims can remove the PIN lock screen with a factory reset but they’ll lose their files. Android device owners who’ve previously rooted their phones however will be better off since they can use the Android Debugging Bridge to remove the file where the ransomware’s PIN is stored.
Both Symantec and ESET note that PornDroid is not available in Google’s Play Store.
Despite being distributed outside of Google Play, PornDroid’s promise has lured enough victims to make for a lucrative operation.
Security researcher Kafiene, who’s chronicled the rise of police locker trojans for Windows, analysed the management interface of several PornDroid campaigns running in December. The researcher found there were an estimated 7,000 devices locked each day by this variant. The percentage of people paying was below 2 percent, but with at least 180,000 Android infections in that month alone, the gang or gangs could have earned up to $500,000 in a month.
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