How to disable the mail() for PHP to help prevent email abuse or outgoing spam

Introduction

You may use the following steps to disable the mail() function in PHP. The use of the mail() function allows a script to send messages without the need to use an existing email account and password.

Via WHM

1. Login to WHM as the root user

2. Navigate to: "Home »Software »MultiPHP INI Editor"

3. Click the "Editor Mode" tab

4. Select a version of PHP from the dropdown

5. Find the setting for disable_functions

6. Add the mail function to that setting. If there are no existing disabled functions, your setting would look like this:

; This directive allows you to disable certain functions for security reasons.
; It receives a comma-delimited list of function names.
; http://php.net/disable-functions
disable_functions = mail

7. Click the blue "Save" button in the upper right area of the editor

Via WHM with PHP-FPM enabled

1. Navigate to  "WHM» Software » MultiPHP Manager"
   
    
2. Click "Manage Settings"
   
3. Scroll down to "Disable Functions"
   
   
4. Add mail to the "Disable Functions"
   

Via SSH or Terminal

1. Login to the server via SSH or Terminal

2. Use the following command to show a list of the php.ini configurations for each of your versions of PHP:

find /opt/cpanel/ea-php* -name "php.ini"

3. Open one of the php.ini files with the text editor of your choice

4. Edit the disable_functions option. If you only want to disable the mail function, it would look like this:

; This directive allows you to disable certain functions for security reasons.
; It receives a comma-delimited list of function names.
; http://php.net/disable-functions
disable_functions = mail