Note: This notes were made using the following books: “CISPP Study Guide” and “CISSP for dummies”.
The Information Security Governance and Risk Management domain focuses on risk analysis and mitigation. This domain also details security governance, or the organizational structure required for a successful information security program.
- Confidentiality seeks to prevent the unauthorized disclosure of information. In other words, confidentiality seeks to prevent unauthorized read access to data.
- Integrity seeks to prevent unauthorized modification of information. In other words, integrity seeks to prevent unauthorized write.
- Availability ensures that information is available when needed.
The CIA triad may also be described by its opposite: Disclosure, Alteration, and Destruction (DAD).
The term “AAA” is often used, describing cornerstone concepts Authentication, Authorization, and Accountability.
- Authorization describes the actions you can perform on a system once you have identified and authenticated.
- Accountability holds users accountable for their actions. This is typically done by logging and analyzing audit data
- Nonrepudiation means a user cannot deny (repudiate) having performed a transaction. It combines authentication and integrity: nonrepudiation authenticates the identity of a user who performs a transaction, and ensures the integrity of that transaction. You must have both authentication and integrity to have nonrepudiation.
Least privilege means users should be granted the minimum amount of access (authorization) required to do their jobs, but no more.
Need to know is more granular than least privilege: the user must need to know that specific piece of information before accessing it.
Defense-in-Depth (also called layered defenses) applies multiple safeguards (also called controls: measures taken to reduce risk) to protect an asset.
- Assets are valuable resources you are trying to protect.
- A threat is a potentially harmful occurrence, like an earthquake, a power outage, or a network-based worm. A threat is a negative action that may harm a system.
- A vulnerability is a weakness that allows a threat to cause harm.
Risk = Threat × Vulnerability
To have risk, a threat must connect to a vulnerability.
The “Risk = Threat × Vulnerability” equation sometimes uses an added variable called impact: “Risk = Threat × Vulnerability × Impact.”
Impact is the severity of the damage, sometimes expressed in dollars.
Loss of human life has near-infinite impact on the exam. When calculating risk using the “Risk = Threat × Vulnerability × Impact” formula, any risk involving loss of human life is extremely high, and must be mitigated.
The Annualized Loss Expectancy (ALE) calculation allows you to determine the annual cost of a loss due to a risk. Once calculated, ALE allows you to make informed decisions to mitigate the risk.
The Asset value (AV) is the value of the asset you are trying to protect.
The Exposure Factor (EF) is the percentage of value an asset lost due to an incident.
The Single Loss Expectancy (SLE) is the cost of a single loss. SLE = AV x EF.
The Annual Rate of Occurrence (ARO) is the number of losses you suffer per year.
The Annualized Loss Expectancy (ALE) is your yearly cost due to a risk. It is calculated by multiplying the Single Loss Expectancy (SLE) times the Annual Rate of Occurrence (ARO).
The Total Cost of Ownership (TCO) is the total cost of a mitigating safeguard. TCO combines upfront costs (often a one-time capital expense) plus annual cost of maintenance, including staff hours, vendor maintenance fees, software subscriptions, etc.
The Return on Investment (ROI) is the amount of money saved by implementing a safeguard.
Once we have assessed risk, we must decide what to do. Options include accepting the risk, mitigating or eliminating the risk, transferring the risk, and avoiding the risk.
Quantitative and Qualitative Risk Analysis are two methods for analyzing risk. Quantitative Risk Analysis uses hard metrics, such as dollars. Qualitative Risk Analysis uses simple approximate values. Quantitative is more objective; qualitative is more subjective.
The risk management process
Risk Management Guide for Information Technology Systems (see http://csrc.nist.gov/publications/nistpubs/800-30/sp800-30.pdf).
The guide describes a 9-step Risk Analysis process:
1. System Characterization – System characterization describes the scope of the risk management effort and the systems that will be analyzed.
2. Threat Identification –
Threat Identification and Vulnerability Identification, identify the threats and vulnerabilities, required to identify risks using the “Risk = Threat × Vulnerability” formula.
3. Vulnerability Identification
4. Control Analysis – Control Analysis, analyzes the security controls (safeguards) that are in place or planned to mitigate risk.
5. Likelihood Determination
6. Impact Analysis
7. Risk Determination
8. Control Recommendations
9. Results Documentation
Information Security Governance
Information Security Governance is information security at the organizational level.
Security Policy and related documents
- Policies are high-level management directives. Policy is high level: it does not delve into specifics. All policy should contain these basic components: Purpose, Scope, Responsibilities , Compliance. NIST Special Publication 800-12 (see http://csrc.nist.gov/publications/nistpubs/800-12/800-12-html/chapter5.html) discusses three specific policy types: program policy, issue-specific policy, and system-specific policy. Program policy establishes an organization’s information security program.
- A procedure is a step-by-step guide for accomplishing a task. They are low level and specific. Like policies, procedures are mandatory.
- A standard describes the specific use of technology, often applied to hardware and software. Standards are mandatory. They lower the Total Cost of Ownership of a safeguard. Standards also support disaster recovery.
- Guidelines are recommendations (which are discretionary).
- Baselines are uniform ways of implementing a safeguard.
Roles and responsibilities
Primary information security roles include senior management, data owner, custodian, and user.
- Senior Managementcreates the information security program and ensures that is properly staffed, funded, and has organizational priority. It is responsible for ensuring that all organizational assets are protected.
- The Data Owner (also called information owner or business owner) is a management employee responsible for ensuring that specific data is protected. Data owners determine data sensitivity labels and the frequency of data backup. The Data Owner (capital “O”) is responsible for ensuring that data is protected. A user who “owns” data (lower case “o”) has read/write access to objects.
- A Custodian provides hands-on protection of assets such as data. They perform data backups and restoration, patch systems, configure antivirus software, etc. The Custodians follow detailed orders; they do not make critical decisions on how data is protected.
- Users must follow the rules: they must comply with mandatory policies procedures, standards, etc.
Complying with laws and regulations is a top information security management priority: both in the real world and on the exam.
The exam will hold you to a very high standard in regard to compliance with laws and regulations. We are not expected to know the law as well as a lawyer, but we are expected to know when to call a lawyer.
The most legally correct answer is often the best for the exam.
Privacy is the protection of the confidentiality of personal information.
Due care and Due Diligence
Due care is doing what a reasonable person would do. It is sometimes called the “prudent man” rule. The term derives from “duty of care”: parents have a duty to care for their children, for example. Due diligence is the management of due care.
Due care is informal; due diligence follows a process.
Gross negligence is the opposite of due care. It is a legally important concept. If you suffer loss of PII, but can demonstrate due care in protecting the PII, you are on legally stronger ground, for example.
Auditing and Control Frameworks
Auditing means verifying compliance to a security control framework (or published specification).
A number of control frameworks are available to assist auditing Risk Analysis. Some, such as PCI (Payment Card Industry), are industry-specific (vendors who use credit cards in the example). Others, such as OCTAVE, ISO 17799/27002, and COBIT.
OCTAVE stands for Operationally Critical Threat, Asset, and Vulnerability Evaluation, a risk management framework from Carnegie Mellon University. OCTAVE describes a three-phase process for managing risk. Phase 1 identifies staff knowledge, assets, and threats. Phase 2 identifies vulnerabilities and evaluates safeguards. Phase 3 conducts the Risk Analysis and develops the risk mitigation strategy. OCTAVE is a high-quality free resource which may be downloaded from: http://www.cert.org/octave/ ISO 17799 and the ISO 27000 Series.
ISO 17799 had 11 areas, focusing on specific information security controls:
2. Organization of information security
3. Asset management
4. Human resources security
5. Physical and environmental security
6. Communications and operations management
7. Access control
8. Information systems acquisition, development, and maintenance
9. Information security incident management
10. Business continuity management
11. Compliance3 ISO 17799 was renumbered to ISO 27002 in 2005, to make it consistent with the 27000 series of ISO security standards.
Simply put, ISO 27002 describes information security best practices (Techniques), and ISO 27001 describes a process for auditing (requirements) those best practices.
COBIT (Control Objectives for Information and related Technology) is a control framework for employing information security governance best practices within an organization. COBIT was developed by ISACA (Information Systems Audit and Control Association.
ITIL(Information Technology Infrastructure Library) is a framework for providing best services in IT Service Management (ITSM). ITIL contains five “Service Management Practices—Core Guidance” publications: • Service Strategy • Service Design • Service Transition • Service Operation • Continual Service Improvement
Certification and Accreditation
Certification is a detailed inspection that verifies whether a system meets the documented security requirements.
Accreditation is the Data Owner’s acceptance of the risk represented by that system.