What is the principle of least privilege. Why is it important?

The Least Privilege Principle declares that a subject should have access to the minimum privilege required to complete a specific task. If no access right is needed, the subject won’t have it. Moreover, the functional management of the subject will control the assignment of rights. 

Also known as the Principle of Minimal Privilege or the Principle of Least Authority, the Principle of Least Privilege (PoLP) is a fundamental concept in computer security and access control. It states that a user or process should only be given the minimum privileges necessary to perform their intended tasks and nothing more.

The principle is based on the idea that granting excessive privileges increases the potential for unauthorized access, misuse, and unintended actions. By adhering to the Principle of Least Privilege, organizations can limit the damage caused by malicious activities, accidental errors, or software vulnerabilities.

One of the key aspects of the Principle of Least Privilege is granting the minimum necessary access. This involves carefully assessing the requirements of each user or process and determining the precise permissions and privileges they need to fulfill their designated functions. For example, an employee in a company’s finance department may only require read and write access to financial records, while a system administrator may require elevated privileges for system maintenance. By implementing the principle, unnecessary privileges are avoided, minimizing the potential for unauthorized access or unintended actions.

Here are some more key aspects of the Principle of Least Privilege:

1. Minimum necessary access: Users and processes should have only the permissions and privileges required to fulfill their specific duties or tasks. This minimizes the potential impact of compromised accounts or malicious actions.
2. Access control granularity: Access controls should be defined at a fine-grained level, allowing administrators to precisely specify the privileges granted to each user or process. This ensures that users only have access to the specific resources they need.
3. Regular review and audit: Privileges should be periodically reviewed and adjusted as needed. This helps maintain the principle over time and ensures that users do not accumulate unnecessary privileges.
4. Separation of duties: Sensitive tasks should be divided among multiple users or processes to avoid concentration of power. This reduces the risk of insider threats and makes it more difficult for a single individual to compromise the system.