Information Security Controls
Types of Controls
|A Vulnerability is a defect in a process, system, application or other asset that creates the potential for loss or harm. Vulnerabilities are measured primarily through the identification of control deficiencies (defects or weaknesses) to determine a system’s or process’ propensity for failure.|
In terms of taxonomy, there are three, commonly accepted forms of Controls:
- Administrative – These are the laws, regulations, policies, practices and guidelines that govern the overall requirements and controls for an Information Security or other operational risk program. For example, a law or regulation may require merchants and financial institutions to protect and implement controls for customer account data to prevent identity theft. The business, in order to comply with the law or regulation, may adopt policies and procedures laying out the internal requirements for protecting this data, which requirements are a form of control.
- Logical – These are the virtual, application and technical controls (systems and software), such as firewalls, anti virus software, encryption and maker/checker application routines.
- Physical – Whereas a firewall provides a “logical” key to obtain access to a network, a “physical” key to a door can be used to gain access to an office space or storage room. Other examples of physical controls are video surveillance systems, gates and barricades, the use of guards or other personnel to govern access to an office, and remote backup facilities.
All three of these elements are critical to the creation of an effective control environment. However, these elements do not provide clear guidance on measuring the degree to which the controls mitigate the risk. Instead, the Simple Risk Model utilizes an alternative set of elements that provide a better means of weighting the level of mitigation:
- Preventive – These are controls that prevent the loss or harm from occurring. For example, a control that enforces segregation of responsibilities (one person can submit a payment request, but a second person must authorize it), minimizes the chance an employee can issue fraudulent payments.
- Detective – These controls monitor activity to identify instances where practices or procedures were not followed. For example, a business might reconcile the general ledger or review payment request audit logs to identify fraudulent payments.
- Corrective – Corrective controls restore the system or process back to the state prior to a harmful event. For example, a business may implement a full restoration of a system from backup tapes after evidence is found that someone has improperly altered the payment data.
Of the three types of controls, preventative controls are clearly the best, since they minimize the possibility of loss by preventing the event from occurring. Corrective controls are next in line, since they minimize the impact of the loss by restoring the system to the point before the event. However, the restoration procedure may result in some degree of loss, since the restoration procedure may lead to the unavailability of systems and applications along with possible lost productivity, customer dissatisfaction, etc. The least effective form of control, but the one most frequently used, is detective controls – identifying events after they have happened. Depending on how soon the detective control is invoked after an event, a business may uncover a loss long after there is any opportunity to limit the amount of damages. In the Proof-of-Concept application, the Control is weighted by whether it is a preventative, detective or corrective control.
One other valuable distinction to be made with controls is whether they are manual or automated. A business can implement manual controls to minimize the chance of fraudulent payments, such as requiring an administrator and a manager to manually sign the applicable paperwork to indicate that the transaction was authorized and approved. As an alternative, the business could automate these controls by introducing a computer program with logical access, segregation of duties and maker/checker controls.