id: "SA-08(02)" title: "Least Common Mechanism" family: "SA" family_name: "System and Services Acquisition" sort_id: "sa-08.02" priority: "P1" implementation_level: "system" parent: "SA-08" enhancement: True
Statement
Implement the security design principle of least common mechanism in {{ insert: param, sa-08.02_odp }}.
Guidance
The principle of least common mechanism states that the amount of mechanism common to more than one user and depended on by all users is minimized POPEK74 . Mechanism minimization implies that different components of a system refrain from using the same mechanism to access a system resource. Every shared mechanism (especially a mechanism involving shared variables) represents a potential information path between users and is designed with care to ensure that it does not unintentionally compromise security SALTZER75 . Implementing the principle of least common mechanism helps to reduce the adverse consequences of sharing the system state among different programs. A single program that corrupts a shared state (including shared variables) has the potential to corrupt other programs that are dependent on the state. The principle of least common mechanism also supports the principle of simplicity of design and addresses the issue of covert storage channels LAMPSON73.
Assessment Objective
{{ insert: param, sa-08.02_odp }} implement the security design principle of least common mechanism.
System and services acquisition policy
procedures addressing the security design principle of least common mechanism used in the specification, design, development, implementation, and modification of the system
system design documentation
security and privacy requirements and specifications for the system
system security and privacy architecture
system security plan
other relevant documents or records
Organizational personnel with the responsibility for determining system security and privacy requirements
organizational personnel with system specification, design, development, implementation, and modification responsibilities
system developers
organizational personnel with information security responsibilities
Organizational processes for applying the security design principle of least common mechanism in system specification, design, development, implementation, and modification
mechanisms supporting the application of the security design principle of least common mechanism in system specification, design, development, implementation, and modification