What Does Fileless Malware Mean?
Fileless malware is a type of malware that operates without the use of a traditional executable file. Instead, fileless malware uses exploits, macros or other means to generate an attack vector without an actual executable file being downloaded and installed by a user.
Techopedia Explains Fileless Malware
There are many different kinds of fileless malware. In general, hackers can use an exploit in a legitimate application that creates unauthorized access or activity. For example, using a macro or extension, hackers can generate malware scripts without requiring the download of an executable file. Some fileless malware attacks are done with existing memory. Others may include aspects of spear-phishing or other types of social engineering hacking. The commonality is that they do not include the traditional type of malware which is resident on a given file or folder that gets transferred into a user system by specific user events.