TLCTC Blog - 2025/02/14

Critical Analysis: FAIR Integration with TLCTC

Overview

FAIR (Factor Analysis of Information Risk) provides a robust framework for quantifying information security risk but lacks a structured approach to threat categorization and struggles with modeling complex attack sequences. The TLCTC framework, using its `TLCTC-XX.YY` enumeration, can enhance FAIR's capabilities by providing both precise threat categorization and a methodology for understanding attack sequences.

Current State Analysis

FAIR's Strengths

  • Strong quantitative risk analysis methodology
  • Clear framework for calculating loss magnitude
  • Established approach to control effectiveness evaluation
  • Proven methodology for risk prioritization

FAIR's Limitations

  • Lacks explicit, standardized threat categorization
  • Struggles with modeling complex, multi-stage attacks
  • Limited ability to represent parallel threat execution
  • Oversimplified view of attack sequences
  • Difficulty in modeling threat interdependencies

TLCTC's Complementary Capabilities

  • Precise threat categorization through 10 distinct clusters (e.g., TLCTC-01.00 to TLCTC-10.00)
  • Clear attack sequence notation using cluster identifiers (e.g., TLCTC-09.00 -> TLCTC-03.00 -> TLCTC-07.00)
  • Support for parallel threat execution (e.g., (TLCTC-01.00 + TLCTC-07.00))
  • Bow-tie model separating causes from consequences
  • Structured approach to control mapping via NIST CSF functions

Enhanced Integration Framework

1. Risk Quantification Enhancements

Sequence Complexity Factor (SCF)

  • Accounts for attack path length and complexity (using TLCTC sequences)
  • Incorporates parallel threat execution (using TLCTC notation)
  • Adjusts base risk calculations for complex scenarios

Compound Threat Multipliers (CTM)

  • Models simultaneous threat execution (e.g., (TLCTC-01.00 + TLCTC-07.00))
  • Accounts for threat synergy effects
  • Enhances probability calculations for complex attacks

Path Variance Analysis (PVA)

  • Evaluates multiple potential attack paths (represented by TLCTC sequences)
  • Weights alternative attack sequences
  • Provides more accurate total risk assessment

Control Effectiveness Matrices (CEM)

  • Maps control effectiveness across multiple TLCTC clusters
  • Accounts for sequence position in effectiveness calculations
  • Provides more accurate defense capability assessment

2. Implementation Framework

Phase Activities
Threat Modeling Phase
  • Use TLCTC enumeration to identify relevant threat clusters (e.g., TLCTC-02.00, TLCTC-04.00)
  • Map potential attack sequences using TLCTC identifiers (e.g., TLCTC-09.00 -> TLCTC-03.00 -> TLCTC-07.00)
  • Identify parallel threat executions (e.g., (TLCTC-01.00 + TLCTC-07.00))
  • Document control mappings against specific TLCTC clusters
Risk Analysis Phase
  • Apply SCF based on TLCTC sequence length/complexity
  • Incorporate CTM for parallel threats identified via TLCTC notation
  • Perform PVA evaluating alternative TLCTC sequences
  • Apply CEM based on control effectiveness per TLCTC cluster in the sequence
Risk Reporting Phase
  • Document primary attack sequences using TLCTC notation
  • Map controls to specific TLCTC clusters
  • Calculate enhanced risk scores incorporating TLCTC-based factors
  • Prioritize mitigation strategies based on TLCTC analysis

Real-World Application Example

Using the Emotet attack sequence from the whitepaper, now with TLCTC enumeration:

TLCTC-09.00 -> TLCTC-07.00 -> TLCTC-07.00 -> TLCTC-04.00 -> (TLCTC-01.00 + TLCTC-07.00)

(Sequence: Social Engineering -> Malware -> Malware -> Identity Theft -> (Abuse of Functions + Malware))

Enhanced FAIR Analysis

  • Calculate base risk using traditional FAIR
  • Apply SCF for the 5-step sequence identified via TLCTC
  • Apply CTM for the parallel execution (TLCTC-01.00 + TLCTC-07.00)
  • Consider alternative attack paths (PVA) modeled with TLCTC sequences
  • Evaluate control effectiveness across the sequence using CEM mapped to TLCTC clusters

Benefits of Integration

1. More Accurate Risk Quantification

  • Accounts for attack sequence complexity via TLCTC paths
  • Models parallel threat execution per TLCTC notation
  • Considers multiple attack paths defined by TLCTC sequences

2. Improved Control Evaluation

  • Maps controls to specific TLCTC clusters
  • Evaluates effectiveness across TLCTC-defined attack sequences
  • Provides more precise defense planning

3. Enhanced Communication

  • Clear, standardized threat categorization (TLCTC-XX.YY)
  • Standardized attack sequence notation (-> and + with TLCTC IDs)
  • Improved stakeholder understanding

4. Better Resource Allocation

  • More precise risk prioritization informed by TLCTC analysis
  • Clearer control implementation guidance tied to TLCTC clusters
  • Better-informed investment decisions

Specific FAIR Enhancement Proposals (Conceptual with TLCTC Notation)

1. Sequence Complexity Factor (SCF)

# Concept: Adjust risk based on sequence length and parallel steps
# Example using Emotet sequence:
# TLCTC-09.00 -> TLCTC-07.00 -> TLCTC-07.00 -> TLCTC-04.00 -> (TLCTC-01.00 + TLCTC-07.00)
# Sequence_Length = 5 steps
# Parallel_Threats = 1 instance (at the end)
# SCF modifier would reflect this complexity.
                        

2. Compound Threat Multipliers (CTM)

# Concept: Increase probability/impact when threats execute in parallel
# Example: (TLCTC-01.00 + TLCTC-07.00)
# The multiplier reflects the increased risk from executing
# Abuse of Functions and Malware deployment simultaneously.
                        

3. Path Variance Analysis (PVA)

# Concept: Calculate risk for multiple potential paths using TLCTC notation.
# Pegasus campaign path examples:
# Path 1: TLCTC-09.00 -> TLCTC-03.00 -> TLCTC-07.00 (Risk_P1)
# Path 2: (TLCTC-05.00 + TLCTC-04.00) -> TLCTC-03.00 -> TLCTC-07.00 (Risk_P2)
# Path 3: (TLCTC-01.00 + TLCTC-05.00) -> TLCTC-03.00 -> TLCTC-07.00 (Risk_P3)
# Total Risk = Function(Risk_P1, Risk_P2, Risk_P3, ...)
                        

4. Control Effectiveness Matrices (CEM)

# Concept: Evaluate control effectiveness against each specific TLCTC cluster.
# Example Control: Security Awareness Training
# Effectiveness vs TLCTC-09.00 (Social Eng.): Moderate/High
# Effectiveness vs TLCTC-03.00 (Exploiting Client): Low/None
# Effectiveness vs TLCTC-07.00 (Malware): Low/None
# CEM reflects effectiveness per cluster within the attack sequence.
                        

Final Risk Calculation

The final enhanced FAIR risk score conceptually integrates these factors, using TLCTC for structure:

The final enhanced FAIR risk score can be calculated as:
Enhanced_FAIR_Risk = Function(Base_FAIR_Risk, SCF(TLCTC_Seq), CTM(TLCTC_Parallel), PVA(TLCTC_Paths), CEM(TLCTC_Clusters))

(Note: The exact mathematical integration requires specific modeling choices beyond this conceptual outline.)