Chapter 6: IT Security and Risk Management Flashcards
Foundations
- Security is the absence of unbearable risks (DIN 2002)
- Risk is the probability of an adverse future event mulitplied by its magnitude
- Risk is the probability that a particular adverse event occurs during a stated period of time, or results from a particular challenge. The Royal Society (1992)
Why IT Security? NI
„Worldwide around 40% of organizations complain about immaterial damages such as loss of reputation, sinking employee motivation or an adverse effect on business relations. After corruption incidences, more than two thirds of German organizations (68%) suffered these kinds of consequential damage.“
Negative impact of incidents:
- Loss of reputation for company/brand (68%)
- Impairment of business connections (52%)
- Decline in employee moral/motivation (28%)
IT Security Properties
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Confidentiality
- Information about system or its users cannot be learned by an attacker
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Integrity
- The system continues to operate properly, only reaching states that would occur if there were no attacker
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Availability
- Actions by an attacker do not prevent users from having access to use of the system
Management of Information Security
IT security objectives
Methods to achieve Basic Security Service Objectives
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Confidentiality
- Encryption (symmetric vs. asymmetric)
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Integrity
- Hash-Functions
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Authentication
- Knowledge of a secret (e.g.: password)
- Possession of a certain object (e.g.: chip card)
- Human characteristics (e.g.: finger print)
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Availability
- Redundancy
Benefit-cost-relation for IT security
Pareto - becomes imense expensive
Example Threat-Matrix
Example Threat Tree: Stealing Customer Data of ABC Corp.
Defensive Measures
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Security Policies
- What kind of passwords are users allowed to create for use on company systems? How often should they change password?
- Who is allowed to have accounts on company systems?
- What security features must be activated on a computer before it can connect to a company network?
- What services are allowed to operate inside a company’s network?
- What are users allowed to download?
- How is the security policy enforced?
- Further,
Security policy must be accessible to all employees It must be reasonable from the users’ standpoint
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Firewalls
- Prevent unauthorized access to a company’s internal resources
- Located typically at the point of connection between the internal network and the external public network
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Encryption
- Can provide a high degree of protection against a vast majority of potential attackers
- Transmission contents are decrypted by using a “key”
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Patching and Change Management
- Attacks often exploit weaknesses for which patches would already be available
- Timely application of fixes to existing systems
- Intrusion detection and network monitoring
- Helps recognize attacks (when it is taking place or when it has already taken place)
Security Management Guidelines
- Make deliberate security decisions
- Consider security as a moving target
- Practice disciplined change management
- Educate users
- Deploy multi-level technical measures, as many as you can afford
The Issue of Risk
- Risk is neither good or bad – it is just a fact
- Some projects involve more risks than others
- Organizations should be prepared to invest in high risk projects only when the return is high BUT don’t place all your assets in high risk projects
The Question:
- How can one determine a high-risk and a low-risk IT project in the absence of “trusted IT advisors”?
Risk Categorization!!!
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Known risks
- Those risks that can be uncovered after careful evaluation of the project plan, the business and technical environment in which the project is being developed, and other reliable information sources (e.g., unrealistic delivery date)
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Predictable risks
- Those risks that are extrapolated from past project experience (e.g., past turnover)
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Unpredictable risks
- Those risks that can and do occur, but are extremely difficult to identify in advance (e.g., zero-day attack)
The Issue of Project Risks
- Project characteristics
- Applegate, McFarlan and McKenney (1999) refer to three project dimensions which have the primary influence on implementation risk
- project size,
- the degree of new technology involved, and
- the level of problem structure in the project.
Project Characteristics
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Size of project — in terms of workers/years of effort
- This is a simple but important risk dimension measurable in worker/years.
- The interpersonal communications task alone increases exponentially with the size of the team.
- Degree of company-relative technology experience
- There is an education/familiarization cost associated with new or untried:
- tools
- concepts
- hardware features
- suppliers of hardware or software
- communications standards
- There is an education/familiarization cost associated with new or untried:
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Degree of inherent structure
- How well-defined are the project’s outputs?
- How well does the implementation team understand what has been requested?
- Have they built a system like this before (plan to throw one away…)