When working with custom settings, what is a crucial component to consider for security purposes?

The idea that custom settings can bypass standard field security is crucial for understanding their security implications. Custom settings are designed to provide application configuration data and can be used to store information that is applicable across an entire organization or specific to a user or profile.

Since custom settings are not subject to sharing rules or field-level security the same way that standard object records are, they allow certain configurations and settings to be accessible to Apex code, formulas, and certain user interfaces regardless of the standard object security settings. This means that sensitive information stored in custom settings could be exposed if not carefully managed, as they can be accessed programmatically without restrictions applied by the usual sharing rules.

Understanding this characteristic is essential for implementing proper security measures, such as controlling who can create or edit these custom settings and ensuring that no sensitive data is stored in them if it could be potentially exposed.