Management Controller Pepper Hashing for Credential Security
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing computing device access control systems are vulnerable to unauthorized access when user credentials are stored in clear or when salts used for hash values are accessible, allowing attackers to derive credentials.
Innovation Solution
Implementing a separate management controller (BMC) that applies a cryptographic hash function with a pepper, stored securely, to enhance security by generating and managing hash values independently of the computing device's processor, using a secure connection and hardware hash engine.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If user credentials are stored in clear or with accessible salts, then access control functionality is simple and fast, but security against unauthorized access is weakened
Solution Approach 1:
The system separates credential verification into two independent components: the computing device handles initial hash computation with salt, while the management controller performs final verification with pepper. This segmentation distributes security functions across separate hardware entities, preventing single-point compromise while maintaining overall system functionality.
Solution Approach 2:
The management controller acts as an intermediary security layer between the computing device and the credential verification process. It receives hash values from the computing device, applies the pepper secret, and performs final verification, thereby mediating the security enhancement without disrupting the existing access control workflow.
2Reliability
If salts are used to strengthen hash values, then security against credential derivation is improved, but salts stored in the same device create a new vulnerability point
Solution Approach 1:
The system divides the hashing components into separate locations: salt remains with the computing device while pepper is stored exclusively in the management controller. This geographic segmentation of security parameters ensures that compromising one device does not expose all credential protection mechanisms, as the pepper remains inaccessible to attackers who gain access to the computing device.
Solution Approach 2:
The management controller serves as an intermediary that holds the pepper secret and performs final hash verification. By positioning this intermediary with separate security boundaries and access controls, the system creates an additional security perimeter that protects the pepper from attacks targeting the computing device, thereby reducing the overall attack surface.
3Productivity
If hash values are computed and stored centrally, then access verification is efficient, but centralized storage creates a single point of failure
Solution Approach 1:
The credential verification function is segmented between two hardware entities: the computing device computes initial hash values efficiently, while the management controller performs final verification with pepper. This segmentation distributes the verification workload and security criticality across separate systems, eliminating the single point of failure inherent in centralized credential storage while maintaining verification efficiency through coordinated processing.
Data Source
AI summary
In some examples, a management controller includes a communication interface to communicate with a computing device, where the management controller is separate from a processor of the computing device. The management controller includes a management processor to receive, from the computing device, a first hash value that is based on a first hash function applied on an input value and a salt, generate a second hash value based on applying a second hash function on the first hash value and a pepper, and send the second hash value to the computing device.