The Operationally Critical Threat, Asset, and Vulnerability Evaluation (OCTAVE) is a framework for identifying and managing information security risks.
It defines a comprehensive evaluation method that allows an organization to identify the information assets that are important to the mission of the organization, the threats to those assets, and the vulnerabilities that may expose those assets to the threats.
By putting together the information assets, threats, and vulnerabilities, the organization can begin to understand what information is at risk.
With this understanding, the organization can design and implement a protection strategy to reduce the overall risk exposure of its information assets.
As a security framework for determining risk level and planning defenses against cyber assaults, the framework defines a methodology to
help organizations minimize exposure to likely threats,
determine the likely consequences of an attack and deal with attacks that succeed.
OCTAVE is designed to leverage the experience and expertise of people within the organization.
The first step is to construct profiles of threats based on the relative risk that they pose.
The process goes on to conduct a vulnerability assessment specific to the organization.
OCTAVE defines three phases:
Phase 1: Build Asset-Based Threat Profiles
Phase 2: Identify Infrastructure Vulnerabilities
Phase 3: Develop Security Strategy and Plans
The framework has gone through several evolutionary phases since that time, however, the basic principles and goals have remained the same.
The OCTAVE method is based on eight processes that are broken into three phases. In the higher education organizations, it is usually preceded by an exploratory phase (known as Phase Zero) to determine the criteria that will be used during the application of the Octave method.
OCTAVE has two variants; OCTAVE-S and OCTAVE Allegro.
OCTAVE-S, a simplified methodology for smaller organizations that have flat hierarchical structures, and
OCTAVE Allegro, a more comprehensive version for large organizations or those with multilevel structures.
OCTAVE-S has fewer processes, nevertheless adhering to the overall OCTAVE philosophy; thus simplifying application for smaller organizations. OCTAVE Allegro is a later variant which focuses on protecting information-based critical assets.
With the OCTAVE risk assessment method, integration of the organization’s infosec policies and unique business needs becomes possible.
OCTAVE helps organizations tap into operational experience and intelligence to define risks in a business context.
OCTAVE risk assessment leverages organizational know-how of the business process for planning information security.
When outsourcing to external agencies, organizations invariably detach themselves from decision-making, leaving that responsibility to experts who are not accountable in the long run, resulting in poor understanding of the nature of the enterprise’s security posture.
Thus, institutionalized improvement never takes place.
On the other hand, with OCTAVE risk assessment, a core analysis team is required to be formed from among the organization’s employees, effectively enlisting their active participation in the decision-making process.
Using the OCTAVE method for risk assessment,
the core analysis team conducts workshops to gather information from different tiers of the organization for identifying critical assets.
Workshops can be conducted using the structured business communication.
Several iterations of brainstorming sessions are held to leverage collective business acumen and experience.
OCTAVE is self-directed and follows the “most critical assets” approach to risk analysis to prioritize areas of improvement.
It follows the premise of Pareto’s law (the 80-20 principle), which states that 80% of effects come from 20% of the causes.
The OCTAVE risk assessment method is divided into three phases:
Technological view, and
The OCTAVE risk assessment method focuses on speed, since for most businesses, time is money. Targeted workshops yield information on the fundamental, business-critical information assets, to a high degree of con-currency.
This phase has the following processes.
Once OCTAVE establishes assets, areas of concern, which typically have a source and outcome, are defined.
Security requirements to tackle these problems must conform to CIA (confidentiality, integrity and availability) precepts.
Organizational vulnerabilities are then identified by comparing current protection strategies against previously established requirements.
This process is repeated, once each for the senior management, operational management and staff.
The final process is the creation of a threat profile based on the above findings.
This gives a consolidated view of all threats, which is then mapped onto a threat tree, structured to give in-depth insight into the source and outcome of threats under the categories of asset, access, actor, motive and outcome.
This phase involves identifying key infrastructural components for critical assets, and the technological vulnerabilities for key components.
The two steps here are identification and evaluation, wherein the different methods through which compromises may occur are analyzed.
The concluding phase of the OCTAVE risk assessment method involves measurement and classification of individual risks as high, medium or low.
Then, a protection strategy in terms of policies and procedures is developed.
This is followed by a mitigation plan geared towards assets and an action plan defining short-term measures for dealing with breaches.
OCTAVE is a flexible and self-directed risk assessment methodology.
A small team of people from the operational (or business) units and the IT department work together to address the security needs of the organization.
The team draws on the knowledge of many employees to define the current state of security, identify risks to critical assets, and set a security strategy.
It can be tailored for most organizations.
Unlike most other risk assessment methods the OCTAVE approach is driven by operational risk and security practices and not technology. It is designed to allow an organization to:
Direct and manage information security risk assessments for themselves
Make the best decisions based on their unique risks
Focus on protecting key information assets
Effectively communicate key security information
The main advantage that OCTAVE gives an organization is that it can be implemented in parts. Since it is exhaustive, organizations choose to implement portions of the workflow that they find appropriate.
Comprehensive consolidation of the threat profiles is one of the core strengths of the OCTAVE risk assessment method. This provides the key intelligence for threat mitigation under most scenarios.
OCTAVE is more flexible. Probability analyses are "optional," the only requirement being thoroughness; analysis teams are directed to consider a variety of factors that can influence probability, as well as to explicitly determine the exact numerical thresholds for "high," "medium" and "low" probabilities.
Unlike standards such as ISO 27005, OCTAVE does not require focus on all assets, thus saving time and keeping the scope relevant to the business context. OCTAVE risk assessment has been recognized as the preferred methodology for HIPAA compliance, making it relevant to companies that have outsourcing relationships with firms regulated under Health Insurance Portability and Accountability Act (HIPAA).
In summary, this method is most useful when creating a risk-aware corporate culture. The method is highly customizable to an organization’s specific security objectives and risk environment.
Comparing with Risk Engineering approach, OCTAVE have the following drawbacks:
though OCTAVE threat modeling provides a robust, asset-centric view, and organizational risk awareness, the documentation can become voluminous.
OCTAVE lacks scalability – as technological systems add users, applications, and functionality, a manual process can quickly become unmanageable.
it does not produce a detailed quantitative analysis of security exposure.
OCTAVE rates risks, likelihoods and impacts on a three-point scale.
Additionally, OCTAVE implementation requires teams to specifically define for themselves what each of the three points on each respective scale actually mean.
this represents a weakness when compared to Risk Engineering approach, which flat-out tells those who use it what each rating means.