On the ISO2700 forum one user gave a long description of his information gathering process but expressed frustration over what to do with it all all, the assets, the threats and so forth, and trying to make it into a risk assessment.
It was easy for the more experienced of us to see what he was missing.
He was missing something very important -- a RISK MODEL
The model determines what you look for and how it is relevant.
This kind of question keeps coming up, many people are unclear about the Statement of Applicability on ISO-27000.
The SoA should outline the measures to be taken in order to reduce risks such as those mentioned in Annex A of the standard. These are based on 'Controls'.
But if you are using closed-source products such as those from Microsoft, are you giving up control? Things like validation checks and integrity controls are are 'internal'.
Well, its a bit of a word-play.
- SoA contains exclusions on controls that are not applicable because the organization doesn't deal with these problems (ie ecommerce)
- SoA contains exclusions on controls that pose a threat (and risks arise) but cannot be helped (ie A.12.2 Correct processing in applications) and no measures can be taken to reduce these risks.
With this, a record must be present in risk assessments, stating that the risk (even if it is above minimum accepted risk level) is accepted
The key to the SOA is SCOPE.