AT-5: Contacts with Security Groups and Associations

AT-5 requires you to establish, document, and maintain organizational contacts with security groups and associations so your team can rapidly obtain threat intelligence, incident guidance, and security best practices. To operationalize it, assign an owner, define approved groups and communication channels, schedule participation, and retain evidence that the contacts are active and used. ¹

Key takeaways:

• Put an explicit owner and procedure around “security community engagement,” not ad hoc participation. ¹
• Keep auditable proof: who you engage, how often, what you received, and how you routed it into operations. ²
• Make AT-5 actionable by tying security-group inputs to incident response, vulnerability management, and awareness training workflows. ¹

AT-5: contacts with security groups and associations requirement is easy to wave at and surprisingly easy to fail in an assessment because teams treat it as informal networking. Assessors typically want to see that you intentionally maintain external security relationships and that those relationships produce operational value: timely advisories, peer coordination, and actionable guidance that reaches the right internal teams.

This control sits in the Awareness and Training family, but it functions as a “security enablement” requirement: build predictable access to security information outside your walls. For federal information systems and contractor systems handling federal data, AT-5 supports faster detection and response, better defensive configuration, and improved security decision-making because you are plugged into recognized security communities. ¹

Practically, you will implement AT-5 through a small set of decisions: which groups count, who may engage, what channels are approved, how you intake and track advisories, and what evidence you retain. The rest is operating rhythm.

Regulatory text

Requirement excerpt: “NIST SP 800-53 control AT-5.” ²

Operator interpretation: AT-5 expects your organization to maintain contacts with security groups and associations. Translate that into an implementable requirement: define approved external security organizations (e.g., ISAC/ISAO-type communities, professional security associations, peer groups, relevant government/industry coordination bodies), assign accountable roles, and run a repeatable process to receive and act on information shared through those relationships. ¹

What an assessor is really asking: “If something breaks or a new threat emerges, do you have trusted, established routes to credible security guidance outside your organization, and can you prove those routes are live?”

Plain-English requirement interpretation (what “good” looks like)

You need a managed, documented capability to:

1. Engage externally with appropriate security groups and associations.
2. Receive security-relevant information (alerts, advisories, recommended mitigations, lessons learned).
3. Route it internally to the right owners (SOC, IR, vulnerability management, engineering, third-party risk).
4. Record what happened so you can prove the capability is active, not aspirational. ¹

AT-5 does not require you to join every group available. It requires intentional contacts that match your mission, sector, and threat profile, and a process that makes those contacts operationally useful.

Who it applies to (entity and operational context)

AT-5 commonly applies where you have committed to NIST SP 800-53 Rev. 5 as your control baseline, including:

• Federal information systems (civilian or defense) operating under NIST SP 800-53 control requirements. ¹
• Contractor systems handling federal data where customer contracts, security plans, or authorization packages flow down NIST SP 800-53 expectations. ¹

Operationally, AT-5 matters most for:

• Security operations (alerting, detection engineering, incident response coordination)
• Vulnerability management (KEV-style urgency triage, exploit intel, mitigation guidance)
• GRC (risk decisions, control updates, audit readiness)
• Third-party risk management (supply-chain advisories, coordinated disclosure signals)

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

Step 1: Assign ownership and scope

• Name a control owner (often the Security Awareness lead, SOC manager, or GRC control owner depending on your operating model).
• Define scope: which business units/systems are in-scope for the NIST control baseline and will benefit from external security contacts. ¹

Deliverable: an AT-5 control statement in your SSP/control catalog that identifies owner, purpose, and boundaries.

Step 2: Define “approved security groups and associations”

Create criteria so participation is defensible:

• Relevance to your sector/tech stack
• Credibility and moderation standards (to reduce misinformation risk)
• Membership rules and any information-handling constraints
• Communication methods (mailing lists, portals, meetings, secure chat)

Document the list of groups, plus alternates if membership lapses.

Practical tip: include at least one group that produces actionable advisories and one that supports peer coordination during incidents; they serve different needs.

Step 3: Establish approved engagement channels and rules of engagement

Write a short procedure that answers:

• Who can join and represent the organization?
• What tools can they use (corporate email only, approved collaboration tools only)?
• What can be shared externally (redaction rules, no customer data, no sensitive architecture)?
• How to handle TLP or “members-only” restrictions if the group uses them (record handling expectations in your internal procedure even if the external framework is not cited in your program documents). ¹

This is where AT-5 overlaps with incident response comms hygiene: external engagement must not become an uncontrolled data-sharing channel.

Step 4: Build an intake-to-action workflow

Treat external security contacts as an input stream that must land somewhere operational:

• Create a dedicated intake mailbox or ticket queue (e.g., “security-advisories@” or a GRC/SOC queue).
• Define triage ownership (SOC, vuln management, product security).
• Define routing rules:
  • Exploit/advisory relevant to your environment → vulnerability ticket with due date and owner
  • Incident coordination request → IR on-call escalation
  • General guidance → awareness/training update or hardening backlog item ¹

Minimum viable workflow: a queue, a triage owner, and a tracking log that shows disposition.

Step 5: Set a participation cadence and backup coverage

Your procedure should specify:

• Expected monitoring frequency for key channels
• Meeting attendance expectations (if applicable)
• Backup contacts if the primary contact is unavailable
• How you handle role changes (offboarding the contact, transferring memberships)

Avoid fragile implementations where one person’s personal membership is the only “control.”

Step 6: Prove the control works with recurring evidence

Each reporting period (often aligned to your governance cadence), collect and review:

• A sample of advisories received
• Actions taken (tickets created, patches accelerated, detections added)
• “No action” items with documented rationale

This is the difference between “we’re members” and “we operate the control.”

Step 7: Operationalize in your GRC system (make audits easy)

Map AT-5 to:

• Control owner
• Procedure
• Evidence list with refresh expectations
• Systems/teams in scope ¹

If you use Daydream, treat AT-5 like a living control: assign the owner, attach the procedure, and set recurring evidence requests so “contacts” do not become a once-a-year scramble.

Required evidence and artifacts to retain

Keep evidence lightweight but audit-grade. Typical artifacts:

• AT-5 procedure (roles, approved groups, engagement rules, intake workflow) ¹
• List of security groups/associations with membership/points of contact
• Membership proof (invoices, membership confirmations, portal access screenshots, welcome emails)
• Participation proof (meeting invites, attendance logs, conference agendas where relevant, mailing list archives)
• Intake records (tickets, advisory log, email-to-ticket exports)
• Action records linking an external advisory to internal work (IR case, vuln remediation, detection change, hardening change)
• Periodic review notes showing the contacts remain relevant and active

Store evidence in a controlled repository with access restrictions appropriate for any sensitive shared content.

Common exam/audit questions and hangups

Assessors often ask:

• “Which groups are you in, and why those?” Expectation: relevance-based rationale.
• “Who monitors the communications, and what happens to advisories?” Expectation: a defined intake process with traceable outcomes.
• “Show me an example where external info changed your actions.” Expectation: at least one end-to-end example from advisory → triage → remediation/detection.
• “What happens if your primary contact leaves?” Expectation: backup coverage and documented role transfer.
• “How do you prevent sensitive data leakage via these groups?” Expectation: rules of engagement and approved channels. ¹

Frequent implementation mistakes (and how to avoid them)

Mistake 1: Treating AT-5 as a resume line item

Failure mode: “We’re members of X” with no proof of activity or outcomes.
Fix: maintain a small advisory/action log and link items to tickets.

Mistake 2: No internal routing path

Failure mode: advisories land in someone’s inbox and die there.
Fix: route through a queue with a triage owner and documented dispositions.

Mistake 3: Uncontrolled external sharing

Failure mode: engineers share logs, screenshots, or customer-impact details in a forum.
Fix: write rules of engagement and train approved participants on what cannot be shared.

Mistake 4: Single point of failure

Failure mode: one security engineer is the only member and leaves.
Fix: require at least two organizational contacts (primary and alternate) and document handoff steps.

Mistake 5: Evidence gaps at assessment time

Failure mode: you did the work but kept no artifacts.
Fix: define “required evidence” up front and collect it on a set cadence in Daydream or your GRC repository. ¹

Enforcement context and risk implications

No public enforcement cases were provided in the source catalog for AT-5, so treat this as an assurance and resilience control rather than a “headline enforcement” item.

Risk-wise, weak AT-5 implementation tends to show up as:

• Slower awareness of emerging threats relevant to your stack
• Slower access to vetted mitigation guidance during fast-moving incidents
• Weaker audit posture because you cannot show how external intelligence is operationalized ¹

A practical 30/60/90-day execution plan

First 30 days (stand up the control)

• Assign AT-5 owner and backup.
• Draft a one-page AT-5 procedure (approved groups, engagement rules, intake workflow).
• Select initial security groups/associations and enroll using organizational accounts.
• Create the intake queue and define triage ownership. ¹

By 60 days (make it operational)

• Start capturing advisories and logging dispositions.
• Run one tabletop-style walk-through: “Advisory arrives, who does what next?”
• Add AT-5 to your control monitoring calendar and evidence repository.
• Train approved participants on rules of engagement and information-sharing boundaries. ¹

By 90 days (prove it works and harden it)

• Produce at least one end-to-end example showing advisory → internal ticket → implemented change.
• Review the group list for relevance; remove low-signal memberships.
• Add management reporting: summary of advisories received and actions taken for the period.
• If using Daydream, set recurring evidence tasks (membership validation, participation proof, sample advisory-to-action trace) so audits are routine. ¹

Frequently Asked Questions

What counts as a “security group or association” for AT-5?

Any credible external security community that provides relevant advisories, coordination, or best practices can count if you document why it is relevant and show active participation. Keep the definition in your AT-5 procedure. ¹

Do we have to join an ISAC to satisfy AT-5?

NIST SP 800-53 does not mandate a specific organization in the provided text. You need documented, maintained contacts with appropriate groups and proof the contacts are operational. ¹

We receive threat intel from a paid provider. Does that satisfy AT-5?

It can support the objective, but AT-5 is specifically about contacts with groups and associations. If you count a provider, document the relationship as an ongoing contact and show how outputs are ingested and acted on. ¹

How do we show “active” participation without exposing sensitive forum content to auditors?

Keep metadata evidence: membership confirmation, meeting invites/attendance, and internal tickets created from advisories. If content is restricted, retain sanitized summaries and note handling restrictions in your procedure. ¹

Who should own AT-5: Security Awareness, SOC, or GRC?

Put ownership where the intake-to-action workflow lives. Many organizations assign the SOC or vuln management as operational owner and GRC as oversight, then document that split in the procedure. ¹

What’s the simplest way to keep AT-5 audit-ready year-round?

Define a short evidence checklist and collect it on a recurring cadence in your GRC system. Daydream can automate reminders and evidence collection so you always have recent participation proof and advisory-to-action examples ready. ¹

Footnotes

1. NIST SP 800-53 Rev. 5

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