Document: NUREG-0800
Document ID: f1629507-6318-4e71-94a6-9d6664ba96a3
Document Type: srp
Title: of the plant safety analysis report (SAR).  Although NRC did not endorse the annexes of
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0706/ML070660327.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.6
CFR Part: 
CFR Title: 

Content:
uctures, and related machine executable representations. The implementation activity addresses hardware configuration and setup; software coding and testing; and communication configuration and set-up [including the incorporation of reused software and commercial off-the-shelf (COTS) products]. 9.4.1 System Features (Regulatory Guide 1.152, Revision 2, Regulatory Position 2.4.1) The developer should ensure that the security design configuration item transformations from the system design specification are correct, accurate, and complete. Appendix 7.1-D-23 March 2007 9.4.2 Development Activities (Regulatory Guide 1.152, Revision 2, Regulatory Position 2.4.2) The developer should implement security procedures and standards to minimize and mitigate tampering with the developed system. The developer’s standards and procedures should include testing with scanning as appropriate, to address undocumented codes or malicious functions that might (1) allow unauthorized access or use of the system or (2) cause systems to behave beyond the system requirements. The developer should account for hidden functions and vulnerable features embedded in the code, and their purpose and impact on the safety system. If possible, these functions should be disabled, removed, or (as a minimum) addressed (e.g., as part of the failure modes and effects analysis of the application code) to prevent any unauthorized access. Scanning is dependent on the platform and code being used, and may not be available for the specified code and compiler. This may be a difficult task with little assurance that the results will be comprehensive and successful in uncovering hidden problems given the size and complexity of most modern computer systems. Pure application code scanning may be partially successful, but many operating systems, machine code, and callable library function aspects of the system may not be able to be successfully scanned and are just as likely to be where avenues for exploitation exist.