Security requirement
- a.Generate error messages that provide information necessary for corrective actions without revealing information that could be exploited.
- b.Reveal error messages only to [Organization-defined: personnel or roles].
Discussion
Organizations consider the structure and content of error messages. The extent to which systems can handle error conditions is guided and informed by organizational policy and operational requirements. Exploitable information includes stack traces and implementation details; erroneous logon attempts with passwords mistakenly entered as the username; mission or business information that can be derived from, if not stated explicitly by, the information recorded; and personally identifiable information, such as account numbers, Social Security numbers, and credit card numbers. Error messages may also provide a covert channel for transmitting information. This requirement is sourced to a control tailored out of the SP 800-53B .13 moderate baseline in SP 800-171.
Tailoring decisions required
Resolve these values through the governing organization’s approved tailoring and risk-management process before declaring the requirement implemented.
Protection strategies supported
These classifications are carried from the official SP 800-172 OSCAL record and help explain the enhanced requirement’s defensive purpose.
Implementation perspective
Treat Error Handling as an enhanced CUI protection outcome for elevated threat conditions that must be reflected in the system boundary, documented implementation, operational behavior, and assessment evidence. Pay particular attention to flaw remediation, malicious-code protection, monitoring, integrity, and trustworthy handling of CUI.
- Confirm the federal agency selected this enhanced requirement for the critical program or high-value asset and identify the CUI system components, services, users, and external connections in scope.
- Resolve every organization-defined parameter through an approved governance and tailoring process.
- Map each clause of the requirement to an accountable owner, implementation mechanism, and evidence source.
- Verify that inherited and shared implementations are supported by current provider evidence and responsibility boundaries.
- Collect evidence during normal operation and review changes, exceptions, and deficiencies on a risk-based cadence.
Questions to ask
- Which critical-program or high-value-asset CUI, data flows, users, and services are protected by this enhanced requirement?
- Which portions are implemented locally, inherited, shared, or not applicable, and what evidence supports that determination?
- Do the system security plan, deployed configuration, operating process, and assessment evidence tell the same story?
- What change, incident, or threshold should trigger reassessment?
Evidence and validation
- patch and remediation records
- malware protection configuration
- monitoring alerts and response records
- integrity validation and exception reports
Common failure patterns
- patch compliance hiding unsupported assets
- alerts generated without response ownership
- exceptions that never expire
- integrity monitoring excluding critical configurations
Assessment objectives and methods
Assessment objectives (2)
- a.
error messages that provide the information necessary for corrective actions are generated without revealing information that could be exploited.
- b.
error messages are revealed only to [Organization-defined: personnel or roles].
Examine
- System and information integrity policy
- system and information integrity procedures
- procedures addressing system error handling
- system design documentation
- system configuration settings and associated documentation
- documentation providing the structure and content of error messages
- system audit records
- system security plan
- other relevant documents or records
Interview
- Personnel responsible for information input validation
- personnel with information security responsibilities
- system/network administrators
- system developers
Test
- Processes for error handling
- automated mechanisms supporting and/or implementing error handling
- automated mechanisms supporting and/or implementing the management of error messages
Source NIST SP 800-53 controls
These controls are referenced by the official SP 800-172 Rev. 3 OSCAL record. Open the corresponding control pages for complete control text, enhancements, D3FEND mappings, and related learning.
Authoritative sources
- NIST SP 800-172 Revision 3 official publication ↗
- NIST SP 800-172A Revision 3 official publication ↗
- NIST OSCAL Content release used for this import ↗
Bare Metal Cyber is an independent educational publisher and is not affiliated with or endorsed by NIST. The official publications, the responsible federal agency, and the governing contract or agreement determine applicability, tailoring, assessment depth, and required implementation.