Attack Graph Analysis for Vehicle Network Security

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for assessing and mitigating security risks in vehicle on-board networks are inefficient due to the complexity of automotive systems, heterogeneity of components, and limitations of existing probability models like Bayesian networks, which struggle to model attacker history, cycles, and cost effectively.

Innovation Solution

A method and system that automatically generate and analyze attack graphs to assess probable attack paths, considering attacker resources and network architecture, using weighted edges to represent attack costs and probabilities, and enabling the identification of critical attack paths for disabling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If Bayesian networks are used to model attack probabilities, then probability estimation is provided, but computational complexity grows exponentially with network size

Engineering Contradiction:
Improveprobability estimationVSAvoidcomputational complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the attack graph into smaller subgraphs or modules that can be analyzed independently. Instead of constructing a single comprehensive Bayesian network for the entire vehicle network, the system divides it into manageable segments (e.g., by control units, network zones, or attack vectors), computes probabilities for each segment separately, and then combines results. This reduces the exponential growth of computational complexity while maintaining probability estimation accuracy.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from a traditional Bayesian network approach (which requires complete probability distribution tables) to a sampling-based probabilistic model. By introducing Monte Carlo sampling or similar probabilistic simulation techniques, the system estimates attack probabilities through repeated random sampling of attack scenarios rather than computing exhaustive probability tables. This dimensional shift from deterministic table-based computation to stochastic simulation reduces computational complexity from exponential to polynomial scale.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If comprehensive security assessments are conducted on vehicle networks, then security risks are identified, but testing and validation become lengthy and expensive

Engineering Contradiction:
Improvesecurity assessmentVSAvoidtesting duration
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent performs preliminary security assessments by automatically generating attack graphs and identifying probable attack paths before actual attacks occur. The system proactively models potential attack scenarios, evaluates their probabilities, and identifies critical vulnerabilities in advance. This preliminary analysis allows security teams to prioritize remediation efforts and conduct focused testing on high-risk areas rather than performing exhaustive testing on the entire network, significantly reducing assessment time while maintaining reliability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent creates a virtual copy or model of the vehicle network in the form of an attack graph that mirrors the actual network's structure, components, and connections. This graphical model serves as a safe virtual environment for conducting security assessments, simulating attacks, and evaluating vulnerabilities without risking the actual vehicle system. The attack graph copy enables comprehensive security analysis to be performed rapidly on the model, with results that can be applied to the real network.

Inventive Principle:
Principle #26Copying

3Reliability

If attack graphs are constructed to model all possible attack combinations, then complete security coverage is achieved, but data collection becomes tedious and inapplicable to embedded systems

Engineering Contradiction:
Improvesecurity coverageVSAvoiddata collection
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent implements self-service mechanisms where the attack graph construction process automatically extracts necessary data from the vehicle network's existing documentation, configuration files, and component specifications. The system autonomously identifies network topology, control unit connections, communication protocols, and potential attack surfaces without requiring manual data collection from embedded systems. This automated data gathering maintains comprehensive security coverage while eliminating the tedious manual data collection process that is incompatible with embedded automotive systems.

Inventive Principle:
Principle #25Self-service

4Reliability

If security measures are deployed to protect all nodes, then network security is improved, but system heterogeneity makes uniform protection difficult

Engineering Contradiction:
Improvenetwork securityVSAvoidsystem heterogeneity
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent applies local quality by tailoring security measures to the specific characteristics of each node, communication protocol, and attack vector within the heterogeneous vehicle network. Instead of implementing uniform security controls across all components, the system identifies the unique properties of each control unit, network segment, and communication interface (e.g., CAN, LIN, Ethernet), and applies appropriately customized security protections. This localized approach accounts for the diverse architectures and protocols in automotive systems while maintaining comprehensive network security.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3490223B1System and method for simulating and foiling attacks on a vehicle on-board network
Publication Date: 2020.04.15 BAYERISCHE MOTOREN WERKE AG
  • EP3490223B1 patent drawingFigure 1~3
  • EP3490223B1 patent drawingFigure 4
  • EP3490223B1 patent drawingFigure 5

AI summary

A method for finding, assessing and foiling attack paths on a vehicle on-board network is provided, wherein components connected on the vehicle on-board network represent nodes of a graph, in which an edge between a first node and a second node is a communication link between the first and the second node, nodes allowing access to the network are start or access nodes, nodes providing specific functions or access to specific functions are asset nodes, and wherein the edge is weighted and the weight of the edge is a cost required to attack the second node from the first through the communication link, a path is formed by at least one node of the graph, and wherein a probability value is determined for the path, for the at least one node of the graph reachable nodes connected to the at least one node are determined, and for each reachable node of the reachable nodes it is determined whether a cumulated cost of the path to the reachable node is within a predefined cost limit, and whether the probability value for the path including the reachable node is within a probability limit, and if this is the case, defining the path to be a probable attack path.