The way INETLOC files are processed by macOS causes them to run commands that are embedded inside, which allows them to execute arbitrary commands without alerts or prompts from the user. These files usually contain a web address and can sometimes contain usernames and passwords for secure shell (SSH) and telnet connections. The security flaw stems from how macOS processes Internet Location (INETLOC) files, which are used as shortcuts to open up various internet locations, like RSS feeds or telnet locations.

Park Minchan, an independent researcher who was credited with the discovery of the security loophole, commented that the mail application isn’t the only possible attack vector, but that the vulnerability could be exploited using any program that could attach and execute files, naming iMessage and Microsoft Office as viable examples. “A vulnerability in macOS Finder allows files whose extension is inetloc to execute arbitrary commands, these files can be embedded inside emails which if the user clicks on them will execute the commands embedded inside them without providing a prompt or warning to the user,” reads the blog by SSD Secure Disclosure about the bug. The security loophole affects all versions of the macOS Big Sur operating system and older systems. Researchers have uncovered a flaw in Apple’s macOS Finder system that could allow remote threat actors to dupe unsuspecting users into running arbitrary commands on their devices. configure -with-libpcap=included in order to use the compatible version included in Nmap, or you should update the libpcap installed on your machine.While Apple did issue a patch for the vulnerability, it seems that the fix can be easily circumvented You may have to configure Nmap with the command. Also, on some newer Mac OS X versions, the libpcap version of the library provided by Apple may be too old. Note that on some older versions of Mac OS X, you may have to replace the command. Once you have installed Xcode and the command-line tools, follow the compilation instructions found in the section called “Linux/Unix Compilation and Installation from Source Code”.

You can install them by opening Xcode from the Applications folder, opening Preferencechoosing the Download header icon and clicking the Install button next to “ Command Line Tools”. Xcode installations don't always include the command line tools. Xcode is not installed by default, but can be downloaded free of Apple's developer tools that include GCC and the rest of the usual build

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