ISO/IEC 27042:2015 provides guidance on the analysis and interpretation of digital evidence in a manner which addresses issues of continuity, validity, reproducibility, and repeatability. It encapsulates best practice for selection, design, and implementation of analytical processes and recording sufficient information to allow such processes to be subjected to independent scrutiny when required. It provides guidance on appropriate mechanisms for demonstrating proficiency and competence of the investigative team.
Analysis and interpretation of digital evidence can be a complex process. In some circumstances, there can be several methods which could be applied and members of the investigative team will be required to justify their selection of a particular process and show how it is equivalent to another process used by other investigators. In other circumstances, investigators may have to devise new methods for examining digital evidence which has not previously been considered and should be able to show that the method produced is “fit for purpose”.
Application of a particular method can influence the interpretation of digital evidence processed by that method. The available digital evidence can influence the selection of methods for further analysis of digital evidence which has already been acquired.
ISO/IEC 27042:2015 provides a common framework, for the analytical and interpretational elements of information systems security incident handling, which can be used to assist in the implementation of new methods and provide a minimum common standard for digital evidence produced from such activities.