Page 1128 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

when administrators create user accounts, they ensure that the
accounts are provisioned with the appropriate amount of resources,

and this includes privileges. Proper user provisioning processes follow
the principle of least privilege.

Aggregation In the context of least privilege, aggregation refers to
the amount of privileges that users collect over time. For example, if a
user moves from one department to another while working for an
organization, this user can end up with privileges from each

department. To avoid access aggregation problems such as this,
administrators should revoke privileges when users move to a
different department and no longer need the previously assigned
privileges.

Transitive Trust A trust relationship between two security domains
allows subjects in one domain (named primary) to access objects in
the other domain (named training). Imagine the training domain has

a child domain named training.cissp. A transitive trust extends the
trust relationship to the child domain. In other words, users in the
primary domain can access objects in the training domain and in the
training.cissp child domain. If the trust relationship is nontransitive,
users in the primary domain cannot access objects in the child
domain. Within the context of least privilege, it’s important to
examine these trust relationships, especially when creating them

between different organizations. A nontransitive trust enforces the
principle of least privilege and grants the trust to a single domain at a
time.

Separation of Duties and Responsibilities

Separation of duties and responsibilities ensures that no single person
has total control over a critical function or system. This is necessary to

ensure that no single person can compromise the system or its
security. Instead, two or more people must conspire or collude against
the organization, which increases the risk for these people.

A separation of duties policy creates a checks-and-balances system
where two or more users verify each other’s actions and must work in
concert to accomplish necessary work tasks. This makes it more