AU-13(3): Unauthorized Replication of Information

AU-13(3) requires you to actively look for signs that external entities (third parties, attackers, former partners, or data brokers) are copying your organization’s information without authorization, using defined discovery techniques, repeatable processes, and supporting tools ¹. To operationalize it quickly, scope what “organizational information” means, stand up monitoring and discovery methods, and retain evidence that you run them and respond.

Key takeaways:

• AU-13(3) is a detection-and-discovery requirement focused on external, unauthorized copying, not internal data handling.
• Auditors will look for a repeatable program: scope, techniques/tools, cadence, triage workflow, and retained results.
• Evidence matters as much as tooling: documented procedures, run logs, findings, and remediation tickets.

The au-13(3): unauthorized replication of information requirement sits in the Audit and Accountability family, but it is not “logging” in the narrow sense. It expects you to discover whether organizational information is being replicated outside your control by an external entity, then prove you have a repeatable way to find and address it ¹. That includes scenarios like stolen data showing up in paste sites, proprietary documents being re-hosted on external file shares, code being copied into public repositories, or customers/partners retaining and reusing data beyond contract terms.

This page translates the requirement into an operator-ready implementation: what to scope, what to deploy, how to triage results, and what evidence to retain for an assessment. The goal is fast operationalization: a control owner can assign responsibilities, select a small set of high-signal discovery techniques, and start producing defensible artifacts without boiling the ocean. Where teams struggle, it is usually not because they lack a security tool. It is because they cannot show the process runs, what it covers, and how they respond when discovery yields a lead.

Regulatory text

Requirement (verbatim): “Employ discovery techniques, processes, and tools to determine if external entities are replicating organizational information in an unauthorized manner.” ¹

What the operator must do:
You need an operating capability (not a one-time project) that:

1. defines what organizational information is in scope,
2. applies discovery techniques (manual and/or automated) to detect external replication,
3. uses processes and tools appropriate to your environment, and
4. produces outcomes you can action (triage, containment, legal/contractual steps, and control improvements) with retained evidence.

Plain-English interpretation

AU-13(3) means: assume some information will escape, then actively hunt for signs it has been copied outside your authorized channels. The focus is “external entities” and “replicating.” This includes adversaries and also legitimate third parties acting outside agreed terms (for example, a service provider retaining datasets after termination, or a partner reusing your data in a new product).

This is not limited to regulated data types. If the information matters to your mission, contractual commitments, security posture, or intellectual property position, it can be in scope. Your scope should be explicit and risk-based.

Who it applies to

Entity types: Federal information systems and contractor systems handling federal data ¹. Practically, any organization adopting NIST SP 800-53 Rev. 5 as its control baseline should implement it ².

Operational contexts where AU-13(3) is most exam-relevant

• Third-party ecosystems: SaaS providers, MSPs, data processors, subcontractors, and integration partners with direct data access.
• Public exposure risk: public code repos, collaboration platforms, externally shared document links, customer support portals, and marketing/knowledge-base content.
• High-value information: sensitive internal docs, system diagrams, credentials/secrets, proprietary source code, vulnerability details, and customer datasets.
• Post-termination risk: offboarding of vendors/partners and employee separations (external replication can occur after access removal).

What you actually need to do (step-by-step)

1) Name the control owner and governance path

• Assign a control owner (often Security Operations, Threat Intelligence, or GRC with SecOps execution).
• Define who can declare a finding “confirmed unauthorized replication” and who approves external notifications (Legal/Privacy/Contracting).
• Document this in a short control procedure that an auditor can read in minutes.

Deliverable: AU-13(3) control procedure with roles/responsibilities and escalation points.

2) Define “organizational information” scope and prioritization

Create an inventory that is good enough to drive discovery. Keep it simple:

• Tier 1 (highest priority): regulated datasets, customer data sets, authentication secrets, private keys, source code, security architecture, incident reports.
• Tier 2: contracts, pricing, internal policies, proprietary research, product roadmaps.
• Tier 3: public or low-impact information (often excluded).

Map each tier to likely replication channels (public web, dark web, code repos, file-sharing, third parties, data brokers). The point is to justify where you look first.

Deliverables: scope statement, tiered list of information types, and discovery coverage matrix.

3) Select discovery techniques (don’t overbuild)

AU-13(3) is flexible on methods; it requires that you employ techniques, processes, and tools ¹. Choose a small set you can run consistently:

High-signal discovery techniques

• External exposure discovery: search for your domains, brands, document fingerprints, and unique internal phrases on public web, paste sites, and code repositories.
• Credential/secrets discovery: detect leaked credentials and API keys associated with your domains and known naming patterns (include repo scanning for accidental publication).
• Third-party replication checks: contract-aligned attestations plus technical validation (for example, verify data deletion or retention settings and export logs upon termination).
• Data loss indicators: look for unusual volumes of outbound data to external destinations, especially to known file-sharing and personal email domains.

Pick what matches your environment and risk model, then make it repeatable.

Deliverable: documented list of discovery techniques with ownership and run frequency (your chosen cadence, consistently followed).

4) Implement tools and integrations that create evidence by default

Tooling should create logs and exportable reports. Examples of tool categories (choose what you already have where possible):

• DLP/CASB alerts for outbound exfil patterns to external services
• SIEM rules for anomalous outbound transfers and “mass download” events
• Threat intel monitoring for leaked credentials/mentions
• Repo scanning for secrets and proprietary code patterns
• Vendor management workflows for offboarding evidence (deletion confirmations, access revocation, and residual data checks)

You are not trying to buy a single “AU-13(3) tool.” You are building an evidence-backed discovery capability.

Deliverables: configuration baselines (rule lists, alert logic descriptions), integration diagram (lightweight), and sample reports.

5) Define a triage workflow and response playbook

Discovery is useless without a decision path. Write a short playbook that covers:

• Intake: how leads arrive (alerts, manual findings, third-party notifications)
• Triage: severity criteria (what makes it critical vs. low)
• Validation: steps to confirm replication (screenshots, hashes, data sampling rules, chain of custody guidance)
• Containment: revoke tokens, rotate secrets, suspend integrations, block egress paths
• Third-party actions: notify the third party, invoke contract clauses, require deletion/attestation, consider audit rights
• Eradication/lessons learned: control fixes (sharing settings, egress rules, least privilege)
• Tracking: ticketing with timestamps and disposition

Deliverables: AU-13(3) triage SOP, incident/ticket templates, and escalation matrix.

6) Run it, track it, and prove it

Assessors commonly fail teams on “paper controls” that never run. Treat AU-13(3) like an operations control:

• Record each run (automated job logs count).
• Store findings, even if “no issues found.”
• Track remediation to closure with tickets.

If you use Daydream to manage third-party risk and control evidence, map AU-13(3) to a control owner, link the procedure, and attach recurring artifacts (for example, monthly discovery reports and triage tickets). That closes the common evidence gap called out for AU-13(3): missing implementation evidence ¹.

Required evidence and artifacts to retain

Keep evidence that proves: scope, execution, and outcomes.

Core artifacts (minimum set)

• AU-13(3) control narrative and procedure (versioned)
• Scope definition of “organizational information” and coverage matrix
• Tool configurations or screenshots showing enabled discovery rules/monitors
• Run evidence: scheduled job logs, alert summaries, monitoring reports, and “no findings” attestations
• Triage and remediation tickets with timestamps, owner, and closure notes
• Third-party communications (as appropriate) and offboarding verification records
• Management review evidence (sign-offs, metrics reviewed, corrective actions assigned)

Evidence hygiene tips

• Store artifacts in a system with access control and immutability or strong change logging.
• Keep raw exports for key findings (screenshots, URLs, hashes) with collection date.

Common exam/audit questions and hangups

Auditors tend to probe these areas because they reveal whether AU-13(3) is operational:

1. “What techniques do you use to discover external replication, and how often do they run?”
2. “Define ‘organizational information’ in scope. Why did you choose that scope?”
3. “Show me evidence of execution, including periods with no findings.”
4. “How do you confirm a replication is unauthorized versus an approved publication?”
5. “What is your response path when the replication involves a third party under contract?”
6. “How do you handle replication in public repositories or community forums?”

Hangup to expect: teams confuse “we have DLP” with “we do external discovery.” AU-13(3) is explicitly about external entities replicating information ¹.

Frequent implementation mistakes and how to avoid them

Mistake	Why it fails	Fix
No written scope for “organizational information”	Assessors can’t tell what you’re protecting or monitoring	Publish a tiered scope and update it through change management
Only internal monitoring (endpoint/SIEM)	Misses replication that already left your boundary	Add external discovery sources and third-party checks
One-time scans during an incident	Control requires an employed process, not ad hoc heroics	Establish recurring runs with saved outputs
Findings tracked in email/slack only	No audit trail; no closure proof	Require ticketing with disposition and evidence attachments
No third-party angle	External entity can be a contractor or partner	Tie AU-13(3) to third-party offboarding and contract enforcement steps

Enforcement context and risk implications

No public enforcement cases were provided in the source catalog for this requirement, so you should treat it as a baseline control expectation rather than a “case law” driven requirement. The risk is still concrete: external replication can create breach notification obligations, contract violations, loss of intellectual property, and downstream compromises (for example, secrets leaked to public repositories). AU-13(3) reduces the “unknown exposure” window by making discovery repeatable ¹.

Practical 30/60/90-day execution plan

You asked for speed; this plan focuses on standing up an auditable program quickly. Adjust the timing to your capacity.

First 30 days (stand up the control skeleton)

• Assign owner(s) and approvers (Security, Legal/Privacy, Procurement).
• Draft AU-13(3) procedure: scope, techniques, tools, triage workflow.
• Choose initial discovery techniques (start with two or three you can run consistently).
• Stand up evidence capture: where reports, logs, and tickets will live.

Exit criteria: documented procedure + first completed run with saved output.

Days 31–60 (operationalize and expand coverage)

• Tune alerting and reduce noise (document tuning decisions).
• Add third-party replication checks into offboarding workflows.
• Train responders and create ticket templates for findings.
• Start monthly management review of results and exceptions.

Exit criteria: recurring runs producing consistent artifacts and tracked remediation.

Days 61–90 (make it resilient and assessment-ready)

• Expand to additional channels (repos, paste sites, brand monitoring, data broker checks as appropriate).
• Add quality checks: validate the discovery jobs actually run and results are reviewed.
• Run a tabletop exercise: “external replication found” scenario with Legal/Comms/Procurement.
• Package evidence for auditors: control narrative, last runs, sample finding end-to-end.

Exit criteria: end-to-end proof from discovery to closure, plus a maintained evidence binder (or Daydream control record) mapped to AU-13(3).

Frequently Asked Questions

Does AU-13(3) require a specific tool (DLP, CASB, threat intel platform)?

No. The text requires discovery techniques, processes, and tools, but it does not mandate a specific product ¹. Pick a set that matches your data flows and produces exportable evidence.

What counts as “external entities” under AU-13(3)?

Any party outside your organizational boundary, including third parties under contract and unknown actors. Your procedure should name the categories you consider and how you investigate each.

How do we prove “unauthorized” replication without overstepping legally?

Focus on observable facts (where the data appeared, what it contains, collection timestamps) and route determinations through Legal/Privacy and contract owners. Keep a clear chain of custody for any captured evidence.

If we have no findings, do we still pass the requirement?

Yes, if you can show the discovery process ran as designed and results were reviewed. Retain “no findings” reports, job logs, and reviewer sign-off to prove operation ¹.

How does this relate to third-party risk management?

External replication often occurs through third-party access, retention, or reuse. Embed replication checks into onboarding/offboarding, contract terms, and periodic monitoring so you can detect misuse and enforce obligations.

How should we document AU-13(3) in our GRC system?

Record a clear control statement, owner, scope, discovery methods, run frequency, and required evidence. In Daydream, teams commonly attach recurring discovery reports and related tickets to the AU-13(3) control record to close the evidence gap ¹.

Footnotes

1. NIST SP 800-53 Rev. 5 OSCAL JSON

2. NIST SP 800-53 Rev. 5