Trust boundary is a term used in
computer science and
security
Security is protection from, or resilience against, potential harm (or other unwanted coercive change) caused by others, by restraining the freedom of others to act. Beneficiaries (technically referents) of security may be of persons and social ...
which describes a boundary where program data or execution changes its level of "trust," or where two principals with different capabilities exchange data or commands. The term refers to any distinct boundary where within a
system
A system is a group of Interaction, interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment (systems), environment, is described by its boundaries, ...
all sub-systems (including data) have equal trust.
An example of an execution trust boundary would be where an application attains an increased
privilege level
In computer science, hierarchical protection domains, often called protection rings, are mechanisms to protect data and functionality from faults (by improving fault tolerance) and malicious behavior (by providing computer security).
Computer ...
(such as
root).
A data trust boundary is a point where data comes from an untrusted source--for example, user input or a
network socket.
A "trust boundary violation" refers to a
vulnerability where computer
software trusts data that has not been validated before crossing a boundary.
References
Computer security
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