An existing version of the Android device screen-locking malware SLocker has apparently been copied and repackaged in the form of a mobile coronavirus app, in hopes of drawing in victims and encouraging downloads from third-party marketplace sites.
Researchers at Bitdefender found the malicious app, which has been targeting users in Ukraine, Russia, Kazakhstan, Turkmenistan and and parts of India and North Africa.
The Uzbek-language app, called “Koronavirus haqida” or “About Coronavirus,” confounds its victims by locking the screen, prohibiting access and demanding a ransom payment to restore proper functionality. A ransom note says victims only have 20 minutes to pay before the phone is rendered unusable, but the threat is empty. However, the malware does require some effort to eradicate — it survives a reboot and must be removed via the Android Debug Bridge or Safe Mode.
The ransom note instructs the victim to call a phone number to make a payment and then receive the code to unlock the phone. Strangely, the code, which is hard-coded into SLocker, is the same as the phone number itself, just without the “+” sign.
Back in March, researchers at DomainTools reported a similar scam that infected users with a screen locker by disguising it as an app that supposedly offered statistics on the COVID-19 pandemic and a heat map of outbreak hotspots. According to DomainTools, the malware in that case, dubbed CovidLock, was a newly discovered program, while in this instance, the malware seems to merely be a redressed version of SLocker.
“Users with a voracious appetite consume everything that’s coronavirus-related, and in this case, the app would lock the screen of the phone, prompting people to pay for a code to return the control of their device,” explains a Bitdefender company blog post by analyst Silviu Stahie and researcher Adina Mateescu. “While it’s not as damaging as ransomware, the average user will have a hard time distinguishing between threats, as the result is the same, and that’s getting locked out of your device.”