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IA-4(1) IA · Identification and Authentication

Prohibit Account Identifiers as Public Identifiers

LOW MODERATE HIGH
1 Overlay 2 Related Controls
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Requirements NIST SOURCE

Prohibit the use of system account identifiers that are the same as public identifiers for individual accounts.

Discussion (NIST Supplemental Guidance)

Prohibiting account identifiers as public identifiers applies to any publicly disclosed account identifier used for communication such as, electronic mail and instant messaging. Prohibiting the use of systems account identifiers that are the same as some public identifier, such as the individual identifier section of an electronic mail address, makes it more difficult for adversaries to guess user identifiers. Prohibiting account identifiers as public identifiers without the implementation of other supporting controls only complicates guessing of identifiers. Additional protections are required for authenticators and credentials to protect the account.

Implementation Guidance

Engineering Interpretation

Original engineering commentary written for this explorer — not NIST source text and not authoritative guidance.

No engineering interpretation has been authored for IA-4(1) yet. This section is architected to receive it — see the Requirements and Assessment sections above for the authoritative NIST source content in the meantime.

Assessment

NIST SP 800-53A REV 5.2.0

Assessment Objectives

  1. the use of system account identifiers that are the same as public identifiers is prohibited for individual accounts.

Examine

[SELECT FROM: Identification and authentication policy; system security plan; procedures addressing identifier management; procedures addressing account management; system design documentation; system configuration settings and associated documentation; system audit records; other relevant documents or records].

Interview

[SELECT FROM: Organizational personnel with identifier management responsibilities; organizational personnel with information security responsibilities; system/network administrators].

Test

[SELECT FROM: Mechanisms supporting and/or implementing identifier management].

Overlays

Showing the OT/ICS overlay for the parent control IA-4 — see the IA-4(1) entries within each baseline below.

OT/ICS Overlay SP 800-82r3

NIST SP 800-82r3 Appendix F, Table 22. Blank baseline means the control/control enhancement is not selected in that initial OT baseline.

LOW

  • Base control: Included (matches standard baseline)

MODERATE

  • Base control: Included (matches standard baseline)
  • Included: (4)

HIGH

  • Base control: Included (matches standard baseline)
  • Included: (4)

STIGs & CCIs

No STIG checks or CCI mappings are currently loaded for IA-4(1). This section is architected to display, per product: STIG ID, Finding ID, Severity, Title, Description, Check, Fix, CCI, and NIST control mapping — but nothing is populated here until a real DISA STIG/CCI dataset is ingested.

Learn more about STIG/CCI integration →

Evidence

Potential Evidence — Derived

Categorized from the SP 800-53A "Examine"/"Test" artifact list above by keyword — not an authoritative NIST evidence list.

Policy

  • Identification and authentication policy
  • system security plan

Configuration

  • system design documentation
  • system configuration settings and associated documentation

Testing

  • Mechanisms supporting and/or implementing identifier management

Other Records

  • procedures addressing identifier management
  • procedures addressing account management
  • system audit records
  • other relevant documents or records