Which type of malware resides only in RAM? Explaining fileless malware

Unlike most malware, which requires user installation, fileless malware typically operates without writing anything to the hard drive. 

Explaining malware which resides only in RAM 

Unlike traditional malware, which typically involves downloading and running an executable file, fileless malware operates in the system’s memory (RAM) and often exploits legitimate tools (like PowerShell, WMI, or Windows Registry) and scripts already present on the target system (such as JavaScript or VBScript). 

This means that fileless malware has unique attack vectors, installation, persistence …

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