AU-10 Non-repudiation
Guidance: nonePolicy clause: draftWhat these mean
au10ctl| Baselines | Implementation level | Enhancements |
|---|---|---|
| High | System | 4 (0 in a baseline) |
Related controls: AU-9, PM-12, SA-8, SC-8, SC-12, SC-13, SC-16, SC-17, SC-23
Control statement
Section titled “Control statement”Provide irrefutable evidence that an individual (or process acting on behalf of an individual) has performed [Assignment: organization-defined actions].
NIST discussion
Types of individual actions covered by non-repudiation include creating information, sending and receiving messages, and approving information. Non-repudiation protects against claims by authors of not having authored certain documents, senders of not having transmitted messages, receivers of not having received messages, and signatories of not having signed documents. Non-repudiation services can be used to determine if information originated from an individual or if an individual took specific actions (e.g., sending an email, signing a contract, approving a procurement request, or receiving specific information). Organizations obtain non-repudiation services by employing various techniques or mechanisms, including digital signatures and digital message receipts.
Control enhancements
Section titled “Control enhancements”AU-10(1) Association of Identities
Section titled “AU-10(1) Association of Identities”Baselines: Not in a baseline
- (a) Bind the identity of the information producer with the information to [Assignment: organization-defined strength of binding] ; and
- (b) Provide the means for authorized individuals to determine the identity of the producer of the information.
Discussion and assessment objectives for AU-10(1)
Binding identities to the information supports audit requirements that provide organizational personnel with the means to identify who produced specific information in the event of an information transfer. Organizations determine and approve the strength of attribute binding between the information producer and the information based on the security category of the information and other relevant risk factors.
Determine if:
- AU-10(01)(a) the identity of the information producer is bound with the information to [Assignment: organization-defined strength of binding];
- AU-10(01)(b) the means for authorized individuals to determine the identity of the producer of the information is provided.
Examine: Audit and accountability policy; system security plan; privacy plan; procedures addressing non-repudiation; system design documentation; system configuration settings and associated documentation; system audit records; other relevant documents or records.
Interview: Organizational personnel with information security and privacy responsibilities; system/network administrators; system developers.
Test: Mechanisms implementing non-repudiation capability.
AU-10(2) Validate Binding of Information Producer Identity
Section titled “AU-10(2) Validate Binding of Information Producer Identity”Baselines: Not in a baseline
- (a) Validate the binding of the information producer identity to the information at [Assignment: organization-defined frequency] ; and
- (b) Perform [Assignment: organization-defined actions] in the event of a validation error.
Discussion and assessment objectives for AU-10(2)
Validating the binding of the information producer identity to the information prevents the modification of information between production and review. The validation of bindings can be achieved by, for example, using cryptographic checksums. Organizations determine if validations are in response to user requests or generated automatically.
Determine if:
- AU-10(02)(a) the binding of the information producer identity to the information is validated at [Assignment: organization-defined frequency];
- AU-10(02)(b) [Assignment: organization-defined actions] in the event of a validation error are performed.
Examine: Audit and accountability policy; system security plan; privacy plan; procedures addressing non-repudiation; system design documentation; system configuration settings and associated documentation; validation records; system audit records; other relevant documents or records.
Interview: Organizational personnel with information security and privacy responsibilities; system/network administrators; system developers.
Test: Mechanisms implementing non-repudiation capability.
AU-10(3) Chain of Custody
Section titled “AU-10(3) Chain of Custody”Baselines: Not in a baseline
Maintain reviewer or releaser credentials within the established chain of custody for information reviewed or released.
Discussion and assessment objectives for AU-10(3)
Chain of custody is a process that tracks the movement of evidence through its collection, safeguarding, and analysis life cycle by documenting each individual who handled the evidence, the date and time the evidence was collected or transferred, and the purpose for the transfer. If the reviewer is a human or if the review function is automated but separate from the release or transfer function, the system associates the identity of the reviewer of the information to be released with the information and the information label. In the case of human reviews, maintaining the credentials of reviewers or releasers provides the organization with the means to identify who reviewed and released the information. In the case of automated reviews, it ensures that only approved review functions are used.
Determine if reviewer or releaser credentials are maintained within the established chain of custody for information reviewed or released.
Examine: Audit and accountability policy; system security plan; privacy plan; procedures addressing non-repudiation; system design documentation; system configuration settings and associated documentation; records of information reviews and releases; system audit records; other relevant documents or records.
Interview: Organizational personnel with information security and privacy responsibilities; system/network administrators; system developers.
Test: Automated mechanisms implementing non-repudiation capability.
AU-10(4) Validate Binding of Information Reviewer Identity
Section titled “AU-10(4) Validate Binding of Information Reviewer Identity”Baselines: Not in a baseline
- (a) Validate the binding of the information reviewer identity to the information at the transfer or release points prior to release or transfer between [Assignment: organization-defined security domains] ; and
- (b) Perform [Assignment: organization-defined actions] in the event of a validation error.
Discussion and assessment objectives for AU-10(4)
Validating the binding of the information reviewer identity to the information at transfer or release points prevents the unauthorized modification of information between review and the transfer or release. The validation of bindings can be achieved by using cryptographic checksums. Organizations determine if validations are in response to user requests or generated automatically.
Determine if:
- AU-10(04)(a) the binding of the information reviewer identity to the information at the transfer or release points prior to release or transfer between [Assignment: organization-defined security domains] is validated;
- AU-10(04)(b) [Assignment: organization-defined actions] are performed in the event of a validation error.
Examine: Audit and accountability policy; system security plan; privacy plan; procedures addressing non-repudiation; system design documentation; system configuration settings and associated documentation; validation records; system audit records; other relevant documents or records.
Interview: Organizational personnel with information security and privacy responsibilities; system/network administrators; system developers.
Test: Mechanisms implementing non-repudiation capability.
Withdrawn enhancements: AU-10(5).
Assessment objectives (SP 800-53A)
Section titled “Assessment objectives (SP 800-53A)”Objectives and methods for AU-10
Determine if irrefutable evidence is provided that an individual (or process acting on behalf of an individual) has performed [Assignment: organization-defined actions].
Examine: Audit and accountability policy; system security plan; privacy plan; procedures addressing non-repudiation; system design documentation; system configuration settings and associated documentation; system audit records; other relevant documents or records.
Interview: Organizational personnel with information security and privacy responsibilities; system/network administrators; system developers.
Test: Mechanisms implementing non-repudiation capability.
Policy statement
- The System owner shall ensure the system provides irrefutable evidence that an individual, or a process acting on behalf of an individual, has performed Fill in: actions to be covered by non-repudiation Typical: approving access and changes, signing records, and administering security settings. (AU-10)
From the Audit and Accountability Policy template (draft). Highlighted fields are values your organization sets.
Artifacts
Independent guidance, not an official NIST publication. Control text is from NIST SP 800-53 Rev. 5 and SP 800-53A (public domain). Original content is licensed CC BY 4.0; program templates and the downloadable kit are dedicated to the public domain under CC0 1.0.