PHP › Security
What is the principle of least privilege, and how should it guide decisions about database user permissions and environment configuration in a PHP application?
AdvancedAnswer
The principle of least privilege means every part of a system should only be granted the minimum level of access it genuinely needs to perform its job, and applying this to a PHP application means the database user your application connects with should only have permissions for the specific operations it actually performs, such as select, insert, and update, rather than being granted full administrative rights, and sensitive configuration like database credentials and API keys should be kept outside of publicly accessible files, loaded instead from environment variables or a properly protected configuration file.
// .env file, kept outside the public web root and out of version control
DB_USER=app_readonly
DB_PASS=securepasswordReal-world example A reporting feature that only ever reads data connects to the database using a dedicated read only database user, ensuring that even if that specific part of the application were somehow compromised, an attacker still could not modify or delete any actual data.