Assessing C-I-A values.

[QueryInfoSec]

QueryInfoSec > Information Security > Information Security - Implementation > Assessing C-I-A values.

[Vinod Puthuseeri]

It is a common discussion during an information security risk assessment exercise at most of the organizations. As a general practice the asset value is derived by weighing the confidentiality ©, Integrity (I) and availability (A) value of an asset. While the assets are categorized into Information, Hardware, Software, Service and People, my argument always has been to say that C-I-A values can be assessed for Information Assets only and for all other it should just be the availability value.

Now, let’s look at what is the definition of information assets. Information assets are basically data that is in transit or at rest and also that are available on papers. Having this in mind, I think it is easier to assess the C-I-A values of these assets. Let us take an example:

Contract documents is an information asset or let’s take the file server in an organization, the “data” in the file server is an information asset. How much impact the organization would have, if the information in the document is exposed to unauthorized persons..? – if the impact is less, confidentiality value is less and if the impact is high, confidentiality value is high. Similarly, this is applicable for Integrity and Availability. If the impact is high by losing the integrity or availability, it will be rated high or else low. After determining the C-I-A values the asset value is derived by either taking the highest value or with some simple calculations.

Let’s consider the C-I-A values for a hardware asset. The confidentiality value of the hardware asset is derived by the information that it holds and hence I feel that there would be duplication if we consider the confidentiality value here. We are considering the hardware asset as a whole and hence integrity of the server is not applicable here. Availability value is what we need to consider for an hardware asset.

As we have looked into the hardware asset, the same applies to software and service assets. Now let us look at the people asset.

If we are trying to consider the C-I-A values of a person, let’s say the CEO of the organization, yes he has confidential information. But how do we assess the confidentiality value? It is hard to determine the information that he is holding in his memory and it might also be varying constantly. Which means you cannot determine the “C” either as high or low at given point in time. I am not quite sure about the integrity aspect and coming down to the availability value; this definitely needs to be assessed.

Again, the availability value of people asset according to me should always be set to high, irrespective of his designation, age, gender etc. Why?

Controls are implemented based on the derived risk value. Risk value is proportionate to the asset value, which means if the asset value increases, so does the risk value. In this context, let us take an example:

Contract document (Information Asset) C-I-A = 5 * Threat = 3 * Probability = 3 = 45 (Risk Value)

IT Manager (People Asset) A = 3 * Threat = 3 * Probability = 1 = 9 (Risk Value)

In the above scenario, the information asset has a risk value higher that the people asset. If there is a fire break out in the organization, which of these assets will be well protected or rescued? People will always be considered first during a disaster and hence the asset value of people should always be rated as high. In this case you may ask, we already know that people is first, then why should be even consider listing people asset in the risk assessment exercise? Well, Your thoughts

I would even look to see why we need to consider hardware, software and service assets for the assessment, because all the values are anyway dependent on the information it holds or transmits.

Your thoughts again.

[Anup Narayanan]

Vinod,

Your approach makes sense. But the ground reality is that the practitioner or implementer is caught between 2 opposing forces. Force 1, is the desire to be creative and build an ISMS that makes sense for the business. Force 2, is the fear, or rather what I would call as "audit or certification" phobia. The implementer often feels that the auditor will not support his innovative and useful approach in the name of complying to the standard.

In fact, it is important that implementers become bolder and build an ISMS that they believe in. This may often lead to abandoning or minimizing existing practices and convincing the auditor that though their ISMS may not look like another company's ISMS, it still makes sense to them. Let me share some of my experiences that left me frustrated.

During an audit, the auditor asked for the "risk analysis methodology manual". The client mentioned that the risk analysis methodology is documented in the ISMS manual. The auditor said that the risk analysis methodology has to be a separate document. I went back to the standard and read the standard and it says, "the risk analysis methodology shall be documented". It does not say that it has to be a "separate document". So, what is the end result? Another piece of document is added to the ISMS which will not be opened or read till the next audit. In such situations, the client should have stood up to the auditor and said that they will not create an unnecessary piece of document which is not going to be used.

When I went back to the client, and mentioned this, the client said - "Let us not waste time and let us get over with this audit thingy....".

Similarly,for risk analysis, if the implementer absolutely believes in a new methodology, though it may be different, the implementer must not compromise his belief and position in the name of satisfying auditors. But, how many have the courage?

Thanks,

Anup

[prasanth]

Hi All Friends

Good to find you all

Vinod can throw some Light on Acceptable Risk Factor Limits

Thankyou

P
 

It is a common discussion during an information security risk assessment exercise at most of the organizations. As a general practice the asset value is derived by weighing the confidentiality ©, Integrity (I) and availability (A) value of an asset. While the assets are categorized into Information, Hardware, Software, Service and People, my argument always has been to say that C-I-A values can be assessed for Information Assets only and for all other it should just be the availability value.

Now, let’s look at what is the definition of information assets. Information assets are basically data that is in transit or at rest and also that are available on papers. Having this in mind, I think it is easier to assess the C-I-A values of these assets. Let us take an example:

Contract documents is an information asset or let’s take the file server in an organization, the “data” in the file server is an information asset. How much impact the organization would have, if the information in the document is exposed to unauthorized persons..? – if the impact is less, confidentiality value is less and if the impact is high, confidentiality value is high. Similarly, this is applicable for Integrity and Availability. If the impact is high by losing the integrity or availability, it will be rated high or else low. After determining the C-I-A values the asset value is derived by either taking the highest value or with some simple calculations.

Let’s consider the C-I-A values for a hardware asset. The confidentiality value of the hardware asset is derived by the information that it holds and hence I feel that there would be duplication if we consider the confidentiality value here. We are considering the hardware asset as a whole and hence integrity of the server is not applicable here. Availability value is what we need to consider for an hardware asset.

As we have looked into the hardware asset, the same applies to software and service assets. Now let us look at the people asset.

If we are trying to consider the C-I-A values of a person, let’s say the CEO of the organization, yes he has confidential information. But how do we assess the confidentiality value? It is hard to determine the information that he is holding in his memory and it might also be varying constantly. Which means you cannot determine the “C” either as high or low at given point in time. I am not quite sure about the integrity aspect and coming down to the availability value; this definitely needs to be assessed.

Again, the availability value of people asset according to me should always be set to high, irrespective of his designation, age, gender etc. Why?

Controls are implemented based on the derived risk value. Risk value is proportionate to the asset value, which means if the asset value increases, so does the risk value. In this context, let us take an example:

Contract document (Information Asset) C-I-A = 5 * Threat = 3 * Probability = 3 = 45 (Risk Value)

IT Manager (People Asset) A = 3 * Threat = 3 * Probability = 1 = 9 (Risk Value)

In the above scenario, the information asset has a risk value higher that the people asset. If there is a fire break out in the organization, which of these assets will be well protected or rescued? People will always be considered first during a disaster and hence the asset value of people should always be rated as high. In this case you may ask, we already know that people is first, then why should be even consider listing people asset in the risk assessment exercise? Well, Your thoughts

I would even look to see why we need to consider hardware, software and service assets for the assessment, because all the values are anyway dependent on the information it holds or transmits.

Your thoughts again.

[Vinod Puthuseeri]

Hello Prasanth,

Acceptable risk factors vary from organization to organization. It mainly depends on how much of risk the organization can take. Some of the organization have their own risk appetite or otherwise you will have define a risk appetite based on the outcome of your risk assessment exercise.

The output of the risk assessment will require to be discussed with your senior management to work out the risk appetite and understand what will be their acceptable level of the identified risks.

Regards,

Vinod Puthuseeri