Abstract: A system is provided for determining vulnerability metrics for graph-based configuration security. During operation, the system generates a multi-layer graph for a system with a plurality of interconnected components. The system determines, based on the multi-layer subgraph, a model for a multi-step attack on the system by: calculating, based on a first set of variables and a first set of tunable parameters, a likelihood of exploiting a vulnerability in the system; and calculating, based on a second set of variables and a second set of tunable parameters, an exposure factor indicating an impact of exploiting a vulnerability on the utility of an associated component. The system determines, based on the model, a set of attack paths that can be used in the multi-step attack and recommends a configuration change in the system, thereby facilitating optimization of system security to mitigate attacks on the system while preserving system functionality.

Abstract: A system determines an on/off feature and vulnerability and dependency nodes in a graph which represents a system of components. The feature enables vulnerability nodes based on a probability that a vulnerability will be exploited, and a vulnerability degrades a utility of one or more components based on an exposure factor. The system calculates, for a path in the graph to a component, a loss of utility of a given dimension of multiple dimensions based on a combiner operator and a logic operator. The combiner operator takes inputs which represent a weighted probability that the given dimension is degraded, and the logic operator defines the inputs based on a probability and exposure factor. The system aggregates calculated losses of utility across the multiple dimensions for the system components. The system selects a combination of possible on/off feature values which results in a lowest loss of utility for the components.

Abstract: A system determines, in a graph which represents a system of components: vulnerability nodes representing known vulnerabilities to the system, including exposed and non-exposed vulnerability nodes associated with an exploitation likelihood; and dependency nodes representing components in the system, including direct and indirect dependency nodes associated with an exposure factor indicating an amount of degradation based on exploitation of an associated vulnerability. The system calculates, across all non-exposed vulnerability nodes and all direct dependency nodes, a score which indicates an attack volume based on at least: a respective second likelihood associated with a non-exposed vulnerability node; an exposure factor associated with a dependency node which represents a component directly degraded based on exploitation of a vulnerability; and a loss of utility of the component.

Abstract: A method of authenticating a user that includes initializing the multi-factor authentication system based on an input; presenting a challenge requesting the user to enter a specific authenticator of a sequence of authenticators stored in the multi-factor authentication system, where the stored sequence of authenticators represents a combination of a plurality of authentication factors; receiving an authenticator from the user in response to the challenge; verifying identity of the user by determining whether the received authenticator matches the specific authenticator requested by the challenge; and granting the access based on a determination that the received authenticator matches the specific authenticator requested, or denying the access based on a determination that the received authenticator does not match the specific authenticator requested.

Abstract: A system is provided for determining vulnerability metrics for graph-based configuration security. During operation, the system generates a multi-layer graph for a system with a plurality of interconnected components. The system determines, based on the multi-layer subgraph, a model for a multi-step attack on the system by: calculating, based on a first set of variables and a first set of tunable parameters, a likelihood of exploiting a vulnerability in the system; and calculating, based on a second set of variables and a second set of tunable parameters, an exposure factor indicating an impact of exploiting a vulnerability on the utility of an associated component. The system determines, based on the model, a set of attack paths that can be used in the multi-step attack and recommends a configuration change in the system, thereby facilitating optimization of system security to mitigate attacks on the system while preserving system functionality.

Abstract: A system and method for determining at least one hardening strategy to prevent at least one attack, comprising: performing processing associated with obtaining at least one attack graph, the at least one attack graph comprising at least one goal condition, at least one initial condition, and at least one exploit; performing processing associated with obtaining at least one allowable action that disables the at least one initial condition; performing processing associated with obtaining costs associated with the at least one allowable action; and performing processing associated with utilizing the at least one allowable action to determine at least one recommended strategy from the at least one allowable action taking into account the costs.

Abstract: A system and method for determining at least one hardening strategy to prevent at least one attack, comprising: performing processing associated with obtaining at least one attack graph, the at least one attack graph comprising at least one goal condition, at least one initial condition, and at least one exploit; performing processing associated with obtaining at least one allowable action that disables the at least one initial condition; performing processing associated with obtaining costs associated with the at least one allowable action; and performing processing associated with utilizing the at least one allowable action to determine at least one recommended strategy from the at least one allowable action taking into account the costs.