6.2 Turn on filename extensions

Information

A filename extension is a suffix added to a base filename that indicates the base filename's file format.

Rationale:

Visible filename extensions allows the user to identify the file type and the application it is associated with which leads to quick identification of misrepresented malicious files.

Impact:

The user of the system can open files of unknown or unexpected filetypes if the extension is not visible.

Solution

Perform the following to implement the prescribed state:

Select Finder

Select Preferences

Check Show all filename extensions

Alternatively, use the following command:

defaults write NSGlobalDomain AppleShowAllExtensions -bool true

See Also

https://workbench.cisecurity.org/files/3092

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6b.

Plugin: Unix

Control ID: 35537e230561e0e9931013e0a518cbd14ec727ac3256fccc8886824e7db0e9ea