ST

Security Target (ST). An ST defines information assurance security and functional requirements for the given information system product, which is called the Target of Evaluation (TOE). An ST is a complete and rigorous description of a security problem in terms of TOE description, threats, assumptions, security objectives, security functional requirements (SFRs), security assurance requirements (SARs), and rationales. The SARs are typically given as a number 1 through 7 called Evaluation Assurance Level (EAL), indicating the depth and rigor of the security evaluation, usually in the form of supporting documentation and testing, that the product meets the SFRs.