Highest Risk Security Mode of Operation

B.

In multilevel mode, two or more classification levels of data exist, some people are not cleared for all the data on the system.

Risk is higher because sensitive data could be made available to someone not validated as being capable of maintaining secrecy of that data (i.e., not cleared for it)

In other security modes, all users have the necessary clearance for all data on the system.

Source: LaROSA, Jeanette (domain leader), Application and System Development Security CISSP Open Study Guide, version 3.0, January 2002.

The security modes of operation are different methods used to control access to information based on a system's security level. The different modes of operation include Dedicated Security Mode, System-High Security Mode, Multilevel Security Mode, and Compartmented Security Mode.

Among the given options, the security mode that involves the highest risk is the Compartmented Security Mode.

Compartmented Security Mode (CSM) is a strict security mode in which data is separated into compartments or categories, and access to each compartment is controlled strictly. It is typically used in highly secure environments, such as military or intelligence agencies, where there is a need to protect highly sensitive information. In this mode, users are only granted access to the specific compartments they need to do their jobs, and access is strictly controlled to ensure that users cannot access information they are not authorized to see.

The risk associated with CSM is that if one compartment is breached, the information in that compartment could be compromised, and it could potentially lead to the compromise of other compartments. This is because the information in each compartment is typically highly interconnected, and the compromise of one compartment could lead to the compromise of others. This risk is amplified when a user with access to multiple compartments is compromised, as the attacker could potentially gain access to multiple compartments.

In contrast, System-High Security Mode (SHSM) is a security mode where all users have the same level of access to information. This mode is typically used in environments where there is a need to protect against unauthorized access, but where the information is not highly sensitive. SHSM has lower risk than CSM since there are no compartments to breach, and the security controls can be applied uniformly across the system.

Multilevel Security Mode (MLS) is a security mode that allows users with different security clearances to access the same system. Access controls are put in place to ensure that users can only access information they are authorized to see, and users with lower clearances cannot access information at a higher clearance level. MLS has a moderate risk since there is the potential for users with lower clearances to access information they should not be able to see, but the risk is lower than CSM since there are no compartments to breach.

Dedicated Security Mode (DSM) is a security mode where each user has a dedicated system or network that they use to access information. This mode has the lowest risk since there is no sharing of information between users, and the security controls can be applied uniformly across each dedicated system. However, this mode is also the most expensive to implement since each user needs their own dedicated system.

In conclusion, Compartmented Security Mode involves the highest risk among the given options since a breach of one compartment could lead to the compromise of other compartments.