Granted Patent B2

US 12,192,226 · App. 18/071,431 · Granted Jan 7, 2025

Inventors: Marc E. Mosko (Kensington, CA); Massimiliano Albanese (Potomac, MD); Ibifubara Iganibo (Faifax, VA)

Assignee: Xerox Corporation

H04L63/1433H04L41/0816H04L63/1416H04L63/1425H04L63/1466

Abstract

Claims (117)

1. A computer-executable method, comprising:

determining a feature with one of an on value and an off value;

determining, in a graph which represents a system of components:

vulnerability nodes which represent known vulnerabilities to the system, wherein the feature enables one or more vulnerability nodes based on a respective probability that a respective vulnerability will be exploited; and

dependency nodes which represent the components of the system, wherein a respective vulnerability degrades a utility of one or more components based on an exposure factor, and wherein a respective component depends on zero or more other components based on a weight;

calculating, for a path in the graph to a first component, a loss of utility of a given dimension of multiple dimensions based on:

a combiner operator which takes a first set of inputs which represent a weighted probability that the given dimension is degraded; and

a logic operator which defines the first set of inputs based on at least a respective probability and a respective exposure factor;

aggregating calculated losses of utility for the components of the system for each combination of possible on/off values for one or more features, wherein a respective calculated loss of utility corresponds to a respective dimension of the multiple dimensions; and

selecting a first combination of the possible on/off values for the one or more features which results in a lowest loss of utility for the components.

2. The method of claim 1 ,

wherein the feature comprises a constraint, wherein the one or more features comprise one or more constraints, and wherein the constraint is one of the one or more constraints, and

wherein the constraint is related to a limitation on a configurable parameter for a component of the system of the components.

3. The method of claim 1 , wherein the known vulnerabilities represented by the vulnerability nodes are based on at least one of:

common vulnerabilities and exposures (CVE) based on a national vulnerability database (NVD);

non-CVE vulnerabilities; and

a predefined bad practice or best practice.

4. The method of claim 1 , wherein a dependency between the respective component and a first component upon which the respective component depends is associated with at least one of:

a scaled dependency, in which the respective component degrades in a proportion to how the first component is impacted;

a strict dependency, in which the respective component degrades completely based on how the first component is impacted;

a redundant dependency, in which the respective component degrades if the first component and other components in a redundant pool of resources are impacted; and

a proportional dependency, in which the respective component degrades by a fixed factor if a first component is impacted.

5. The method of claim 1 , wherein the multiple dimensions include at least one of:

a confidentiality dimension;

an integrity dimension; and

an availability dimension.

6. The method of claim 1 ,

wherein the combiner operator determines how the first set of inputs combine to degrade a utility of a given dependency node.

7. The method of claim 1 , wherein the weighted probability represented by the first set of inputs comprises:

for a direct vulnerability in the path, the respective probability and the respective exposure factor; and

for an indirect vulnerability or a direct dependency in the path, the respective probability, the respective exposure factor, and results of a combiner operator for a prior dependency in the path.

8. The method of claim 1 ,

wherein the logic operator determines how a second set of inputs affect the respective exposure factor of a given vulnerability node, and

wherein the second set of inputs comprises a result of the logic operator on one or more respective probabilities.

9. The method of claim 1 , further comprising:

applying an updated configuration for the system based on the calculated loss of utility for the first component or the aggregated calculated losses of utility for the components of the system,

wherein the updated configuration is based on the selected first combination of possible on/off values.

10. The method of claim 1 ,

wherein the graph comprises a multi-layer graph which includes a configuration subgraph, a vulnerability subgraph, and a dependency subgraph,

wherein the vulnerability subgraph includes the vulnerability nodes, and

wherein the dependency subgraph includes the dependency nodes.

11. The method of claim 10 , further comprising:

displaying, on a screen of a user device, one or more interactive elements which allow the user to:

view the multi-layer graph, including the vulnerability nodes, the dependency nodes, directed edges, likelihoods of exploitation associated with vulnerability nodes, exposure factors, weights, and dependency functions in any of the configuration subgraph, the vulnerability subgraph, and the dependency subgraph;

view or modify configuration parameters for the system using a graph generation tool to obtain the one or more configurations;

obtain a calculated loss of utility for any component represented in the multi-layer graph, including across the multiple dimensions;

view the calculated loss for the one or more configurations;

select a first configuration of the one or more configurations; and

view an explanation of evidence associated with the selected first configuration.

12. A computer system comprising:

a processor; and

a storage device storing instructions that when executed by the processor cause the processor to perform a method, the method comprising:

determining a feature with one of an on value and an off value;

determining, in a graph which represents a system of components:

vulnerability nodes which represent known vulnerabilities to the system, wherein the feature enables one or more vulnerability nodes based on a respective probability that a respective vulnerability will be exploited; and

dependency nodes which represent the components of the system, wherein a respective vulnerability degrades a utility of one or more components based on an exposure factor, and wherein a respective component depends on zero or more other components based on a weight;

calculating, for a path in the graph to a first component, a loss of utility of a given dimension of multiple dimensions based on:

a combiner operator which takes a first set of inputs which represent a weighted probability that the given dimension is degraded; and

a logic operator which defines the first set of inputs based on at least a respective probability and a respective exposure factor;

aggregating calculated losses of utility for the components of the system for each combination of possible on/off values for one or more features, wherein a respective calculated loss of utility corresponds to a respective dimension of the multiple dimensions; and

selecting a first combination of the possible on/off values for the one or more features which results in a lowest loss of utility for the components.

13. The computer system of claim 12 , wherein the multiple dimensions include at least one of:

a confidentiality dimension;

an integrity dimension; and

an availability dimension.

14. The computer system of claim 12 ,

wherein the combiner operator determines how the first set of inputs combine to degrade a utility of a given dependency node, and

wherein the weighted probability represented by the first set of inputs comprises:

for a direct vulnerability in the path, the respective probability and the respective exposure factor; and

for an indirect vulnerability or a direct dependency in the path, the respective probability, the respective exposure factor, and results of a combiner operator for a prior dependency in the path.

15. The computer system of claim 12 ,

wherein the logic operator determines how a second set of inputs affect the respective exposure factor of a given vulnerability node, and

wherein the second set of inputs comprises a result of the logic operator on one or more respective probabilities.

16. The computer system of claim 12 , wherein the method further comprises:

applying an updated configuration for the system based on the calculated loss of utility for the first component or the aggregated calculated losses of utility for the components of the system,

wherein the updated configuration is based on the selected first combination of possible on/off values.

17. The computer system of claim 12 ,

wherein the graph comprises a multi-layer graph which includes a configuration subgraph, a vulnerability subgraph, and a dependency subgraph,

wherein the vulnerability subgraph includes the vulnerability nodes, and

wherein the dependency subgraph includes the dependency nodes, and

wherein the method further comprises displaying, on a screen of a user device, one or more interactive elements which allow the user to:

view the multi-layer graph, including the vulnerability nodes, the dependency nodes, directed edges, likelihoods of exploitation associated with vulnerability nodes, exposure factors, weights, and dependency functions in any of the configuration subgraph, the vulnerability subgraph, and the dependency subgraph;

view or modify configuration parameters for the system using a graph generation tool to obtain the one or more configurations;

obtain a calculated loss of utility for any component represented in the multi-layer graph, including across the multiple dimensions;

view the calculated loss for the one or more configurations;

select a first configuration of the one or more configurations; and

view an explanation of evidence associated with the selected first configuration.

18. A non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method, the method comprising:

determining a feature with one of an on value and an off value;

determining, in a graph which represents a system of components:

vulnerability nodes which represent known vulnerabilities to the system, wherein the feature enables one or more vulnerability nodes based on a respective probability that a respective vulnerability will be exploited; and

dependency nodes which represent the components of the system, wherein a respective vulnerability degrades a utility of one or more components based on an exposure factor, and wherein a respective component depends on zero or more other components based on a weight;

calculating, for a path in the graph to a first component, a loss of utility of a given dimension of multiple dimensions based on:

a combiner operator which takes a first set of inputs which represent a weighted probability that the given dimension is degraded; and

a logic operator which defines the first set of inputs based on at least a respective probability and a respective exposure factor;

aggregating calculated losses of utility for the components of the system for each combination of possible on/off values for one or more features, wherein a respective calculated loss of utility corresponds to a respective dimension of the multiple dimensions; and

selecting a first combination of the possible on/off values for the one or more features which results in a lowest loss of utility for the components.

19. The storage medium of claim 18 ,

wherein the combiner operator determines how the first set of inputs combine to degrade a utility of a given dependency node,

wherein the weighted probability represented by the first set of inputs comprises:

for a direct vulnerability in the path, the respective probability and the respective exposure factor; and

for an indirect vulnerability or a direct dependency in the path, the respective probability, the respective exposure factor, and results of a combiner operator for a prior dependency in the path,

wherein the logic operator determines how a second set of inputs affect the respective exposure factor of a given vulnerability node, and

wherein the second set of inputs comprises a result of the logic operator on one or more respective probabilities.

20. The storage medium of claim 18 , wherein the method further comprises:

applying an updated configuration for the system based on the calculated loss of utility for the first component or the aggregated calculated losses of utility for the components of the system,

wherein the updated configuration is based on the selected first combination of possible on/off values,

wherein the graph comprises a multi-layer graph which includes a configuration subgraph, a vulnerability subgraph, and a dependency subgraph,

wherein the vulnerability subgraph includes the vulnerability nodes, and

wherein the dependency subgraph includes the dependency nodes, and

wherein the method further comprises displaying, on a screen of a user device, one or more interactive elements which allow the user to:

view the multi-layer graph, including the vulnerability nodes, the dependency nodes, directed edges, likelihoods of exploitation associated with vulnerability nodes, exposure factors, weights, and dependency functions in any of the configuration subgraph, the vulnerability subgraph, and the dependency subgraph;

view or modify configuration parameters for the system using a graph generation tool to obtain the one or more configurations;

obtain a calculated loss of utility for any component represented in the multi-layer graph, including across the multiple dimensions;

view the calculated loss for the one or more configurations;

select a first configuration of the one or more configurations; and

view an explanation of evidence associated with the selected first configuration.

Assignments (8)

Continuity (2)

References Cited (102)