CSCE 548 Architectural Risk Analysis

1
CSCE 548 Architectural Risk Analysis
2
Reading

• This lecture
• McGraw Chapter 5
• Next lecture
• Secure Software Construction
• Jan Jürjens, Towards Development of Secure
  Systems using UMLsec, http//citeseer.ist.psu.edu/
  536233.html
• Lodderstedt et. al, SecureUML A UML-Based
  Modeling Language for Model-Driven Security,
  http//citeseer.ist.psu.edu/lodderstedt02secureuml
  .html

3
Application of Touchpoints
External Review
3. Penetration Testing
1. Code Review (Tools)
6. Security Requirements
4. Risk-Based Security Tests
2. Risk Analysis
7. Security Operations
2. Risk Analysis
5. Abuse cases
Requirement and Use cases
Architecture and Design
Test Plans
Code
Tests and Test Results
Feedback from the Field
4
Requirement Analysis

• Identify and document the customers requirements
  for a proposed system
• Client brief idea on what the system should do
• Requirement Analyst
• Detailed system requirements
• Implied requirements
• Regulatory requiremetns
• Create Software Requirements Specification (SRS)
• What the product should do

5
Software Requirement Specification

• Functional requirements
• Features a software has
• Implied requirements
• Non-Functional requirements
• Performance, reliability, security, etc.
• Effects quality of product
• Regulatory requirements
• Law, standards, organizational regulation,
  contract, etc.
• External interface requirements
• Interaction with other software and hardware
• Acceptance criteria
• Confirm that the software is working according to
  the clients specification

6
Review SRS

• Cost effective getting the requirements right
• Manual review team of experts (at least 3) for
  1.5- 2 hours/session
• Detection rate of good review 60-90
• More cost effective to do requirement review than
  code testing alone

7
Design Flaws

• 50 of security problems
• Need explicitly identifying risk
• Quantifying impact tie technology issues and
  concerns to business
• Continuous risk management

8
Security Risk Analysis

• Risk analysis identifying and ranking risks
• Risk management number of discrete risk analysis
  exercises, tracking risk, mitigating risks
• Need understanding of business impact

9
Security Risk Analysis

• Learn about the target of analysis
• Discuss security issues
• Determine probability of compromise
• Perform impact analysis
• Rank risks
• Develop mitigation strategy
• Report findings

10
Learn about the target

• Specifications, documents, design, etc.
• Discuss, brainstorm
• Determine major components and security needs
• Use/study software
• Identify threats

11
Discuss security issues

• Argue about how the product works, areas of
  disagreement
• Identify possible vulnerabilities (lists, tools)
• Identify exploits and protection
• Understand security controls (current, planned)

12
Determine probability of compromise

• Attack scenarios
• Historical data
• Balance control against threat

13
Perform impact analysis

• Impact on assets and business goals
• Impact on security posture
• Impact on social sector

14
Rank risk

• Connect to business goals
• Regulatory requirements
• Customers needs
• Capabilities

15
Develop mitigation strategy

• Countermeasures
• Technical
• Societal
• Ecomonics
• Capabilities and preferences

16
Report findings

• Major vs. minor risks
• Decision support for mitigating risk

17
Traditional Risk Analysis

• Financial loss-based
• Balance cost vs. loss
• Mathematically derived risk rating
• Threat, probability, and impact
• Qualitative assessment
• Knowledge-driven or anecdotal factors
• Social Impact

18
Terminology

• Asset object of protection
• Risk probability that the asset will suffer an
  attack
• Threat the actor (agent) who is the source of
  danger
• Vulnerability defect or weakness in the system
• Countermeasures or safeguards management,
  operational, and technical control to protect
  confidentiality, integrity, and availability
• Impact impact on the organization
• Probability likelihood that the event will occur
  (high, medium, low)

19
Knowledge Requirements

• Three basic steps
• Attack resistance analysis
• Attack patterns and exploit graphs
• Ambiguity analysis
• Knowledge of design principles
• Weakness analysis
• Knowledge of security issues
• Forest-level view What does the software do?
• Critical components and interaction between them
• Identify risk related to flaws

20
Risk Calculation

• Financial loss ALE SLE x ARO
• ALE annualized loss expectancy
• SLE single loss expectancy
• ARO annualized rate of occurrence
• Distinguish between attacks based on frequency of
  occurance
• Qualitative risk assessment (e.g., loss of
  reputation, loss of trust, etc.)
• ROI return-on-investment
• Note security is more like insurance it will
  never hit a big payoff

21
Limitations of Traditional Approaches

• Hard to find correct data for statistical
  distribution
• Do not necessarily provide an easy guide
• Modern applications are complex contextual
  variability of risk

22
Modern Risk Analysis

• Address risk as early as possible in the
  requirements level
• Impact
• Legal and/or regulatory risk
• Financial or commercial considerations
• Contractual considerations
• Social Impact
• Requirements must-haves, important-to-have,
  and nice-but-unnecessary-to-have

23
Basic Risk Analysis

• Tailored for specific vulnerabilities
• High-level overview
• Meaningful results
• Cross-tier analysis different trust zones
• Use of deployment pattern
• Decomposing software on a component-by-component
  basis

24
Risk Analysis Practice

• Ad-hoc manner
• Does not scale and not repeatable or consistent
• Depends on knowledge and expertise of analyst
• Results are difficult to compare

25
Attack Resistance Analysis

• Information about known attacks, attack patterns,
  and vulnerabilities known problems
• Identify general flaws using secure design
  literature and checklists
• Map attack patterns based on abuse cases and
  attack patterns
• Identify risk in the architecture using
  checklist
• Understand and demonstrate the viability of known
  attacks

26
Ambiguity Analysis

• Discover new risks
• Parallel activities of team members ? unify
  understanding
• Private list of possible flaws
• Describe together how the system worked
• Need a team of experienced analysts

27
Weakness Analysis

• Understanding the impact of external software
  dependencies
• Middleware
• Outside libraries
• Distributed code
• Services
• Physical environment
• Etc.

28
Social Vulnerability of Computer Attacks
Vipul Gupta
29
Background

• What is Social Vulnerability
• No single definition
• Generally accepted as inability of the society
  to move out of harms way, that is, incase of a
  disaster (or computer attack) how easily can the
  society (or the victim (s)) recover from it
• Why Social Vulnerability
• Every computer attack has economic and social
  impacts
• Social impacts of a computer attack are usually
  not quantifiable

30
Background

• Impacts on our society (examples)
• Death caused by malfunctioning of computer based
  equipment
• Suicide due to losing everything in a computer
  based fraud scheme
• Ruining of ones credit
• Depression, anxiety, other emotional or physical
  health related issues
• Internet Addiction may be caused by the
  presence of computer
• Etc.
• What happens if the computer based system is not
  available for the intended use (DoS or virus
  attacks considered)

31
Importance of Social Vulnerability

• Computers are an essential part of todays life
• Large scale computer attacks will inhibit the
  functioning of the society (yes, they may be
  possible in future)
• Are some sections of the society likely to be
  more damaged in the event of a computer attack ?
  (Ability to recover easily from those attacks)

32
Background

• Research Goal
• Map the social vulnerability of computer attacks
  based on geographical locations within South
  Carolina
• Develop a model for social vulnerability
  assessment of computer attacks (currently no such
  model exists)

33
Background

• Research on Social Vulnerability in Natural
  Disasters
• Extensive research has been done in this area
• Hypothesize the similarities and differences
  between a computer attack and a natural disaster
  (why?)
• Most natural disasters are prone to specific
  geographical areas
• Do computer attacks exhibit the same feature
  (based on the social factors)

34
Research Activities

• Preliminary hypothesis
• Comparison of natural and computer disasters
• Study the factors influencing computer attacks
• Identified 9 factors to indicate vulnerability to
  attacks updates, installed security software,
  malicious email scanning, firewall protection,
  free downloads, P2P sharing, unverified
  downloads, shared system/passwords, system
  maintenance

35
Research Activities

• Considered age, education (computer experience),
  income (wealth) as the social factors influencing
  the vulnerability (/-) to study
• Are some people more prone to computer attacks
  than others?
• Can some people recover from a computer attack
  faster than others?
• Income Education Age
• The 9 factors

36
Next Class

• Expressing Security Needs during design