Criminals are using the new "Beta Bot" malware, which is capable of destroying anti-virus software, to target financial institutions, e-commerce sites, online payment platforms, and social networking sites, the US Federal Bureau of Investigation (FBI) warns.
The new malware blocks PC users' access to security websites and stops anti-virus programmes, which would leave PC vulnerable.
FBI said that the Beta Bot infection vectors include an illegitimate but official looking Microsoft Windows message box flashing, "User Account Control" that requests a user's permission to allow the "Windows Command Processor" to modify the user's computer settings.
"If the user complies with the request, the hackers are able to exfiltrate data from the computer," the agency said.
The new malware could also spread via USB thumb drives or online via Skype, where it sends on the user to compromised sites.
The agency also suggested PC users to run a full system scan with the latest antivirus software on the infected PC.
"If Beta Bot blocks access to security sites, download the latest antivirus updates or a whole new antivirus programme onto an uninfected computer, save it to a USB drive and load and run it on the infected computer," FBI said.
FBI also advised users to consequently re-format the USB drive to remove any traces of the malware.