Answer Description

Some malware, known as Rogue antivirus or Rogue security software, will pretend to be antivirus software in an attempt to trick users into paying a fee to remove malware. Most likely it will just install more malicious software or do nothing (after charging the user of course).

Wikipedia

Rogue security software is a form of malicious software and internet fraud that misleads users into believing there is a virus on their computer and aims to convince them to pay for a fake malware removal tool that actually installs malware on their computer. It is a form of scareware that manipulates users through fear, and a form of ransomware. Rogue security software has been a serious security threat in desktop computing since 2008. An early example that gained infamy was SpySheriff and its clones, such as Nava Shield.