For a long time Scareware was associated with Pop-ups, informing a user that their computer had been infected. Then it would offer a free antivirus scan that if you accepted not only installs malicious malware on your device, but additionally charge you a fee for supposedly removing what was not there in the first place. Unfortunately, this scam remains in various forms with the latest version finding other ways to cash in on fake alerts. Thereby using them as the entry point to technical support scams or prompting their victims to purchase fraudulent apps from a mobile app store. These fake pop ups aren’t just limited to desktop operating systems, but also mobile ones too. For example, fake Android notifications have become a common danger to users. Scammers are combining two mobile attack modes to deliver one convincing threat that is seemingly impossible to escape from. It starts in the form of social engineering and trying to get the victim to download a seemingly legitimate app onto their Android phone. This is then used to send ransomware-based attacks which doesn’t actually encrypt or hold any data to ransom, however it looks like It does. This is called a screen overlay attack and they are an increasingly common way for attackers to execute such ransomware attacks. It involves allowing a user to be locked out from their device until the ransom is met.

One recent threat found recently is called MalLocker.B which was identified by Microsoft security researchers and it involves abusing incoming phone call notifications. In operation to the user, it will seem as if they have an incoming phone call. However, when they press the answer button, it invokes a persistent screen overlay demanding a ransom and preventing access to anything else, including your home screen. Microsoft found that the code written into MalLocker.B would make sure the overlay screen matched the device screen resolution perfectly to make it as believable as possible.

The best way to ultimately avoid this is to not install any malicious apps in the first place. Don’t download anything from unofficial app stores and especially don’t install “cracked” apps. Malicious adverts are a major scam distribution method, so its recommended to use an add blocking plugin on your browser that blocks any known dodgy ads.