Mastering the Incident Response Process: A Deep Dive into the NIST and SANS Frameworks

In OT cybersecurity, a swift and effective response to a security incident can mean the difference between a minor hiccup and a major catastrophe. But a successful response doesn’t happen by accident. It relies on a well-defined, practiced, and understood process.

Welcome to our “Tech Talk” summary, where we break down complex security topics to help you strengthen your threat hunting and security program. Today, we’re exploring the backbone of cybersecurity operations: the incident response (IR) process. We’ll examine the two most respected and widely adopted best-practice models: the NIST model and the SANS model.

The Two Pillars of Incident Response: NIST and SANS

While several frameworks exist, most modern incident response plans are built upon the foundations laid by the National Institute of Standards and Technology (NIST) and the SANS Institute.

Why Does SANS Provide Recommendations on Incident Response?

When it comes to cybersecurity, preparation is more than half the battle—and that’s where the SANS Institute steps in. As a cornerstone of information security education, SANS dedicates itself to equipping organizations with the knowledge and training needed to face today’s complex threat landscape.

SANS offers incident response recommendations to help organizations:

  • Build and maintain readiness against emerging cyber threats
  • Develop and refine the skills of their incident response teams through practical, hands-on guidance
  • Foster a culture of continual learning and preparedness

By sharing proven tactics, comprehensive guidelines, and a wealth of educational resources—from blog articles to advanced training courses—SANS empowers security professionals to respond decisively and effectively. The goal is simple: make sure your organization isn’t just responding to incidents, but confidently steering through them.

The NIST Incident Response Lifecycle (NIST SP 800-61)

NIST Special Publication 800-61, the Computer Security Incident Handling Guide, is a comprehensive document that outlines everything from creating an IR team to coordinating with external parties. At its core is a four-phase incident response lifecycle:

  1. Preparation: Getting your team, tools, and processes ready before an incident occurs.
  2. Detection & Analysis: Identifying an incident, determining its scope, and analyzing its characteristics.
  3. Containment, Eradication, & Recovery: Isolating the threat, removing it from your environment, and restoring normal business operations.
  4. Post-Incident Activity: Learning from the incident to improve future preparedness.

A key feature of the NIST model is its cyclical and flexible nature. The process isn’t strictly sequential. During the “Containment” phase, you may uncover new information that sends you back to “Detection & Analysis” to re-evaluate the scope. This feedback loop acknowledges the reality of complex incidents and builds resilience into the process.

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The SANS “PICERL” Model

The SANS Institute offers a similar six-phase model, affectionately known by the acronym PICERL:

  1. Preparation
  2. Identification
  3. Containment
  4. Eradication
  5. Recovery
  6. Lessons Learned

As you can see, the core concepts are nearly identical to NIST. The primary difference is that SANS splits NIST’s “Containment, Eradication, & Recovery” phase into three distinct steps. This is largely a notational difference; the underlying intent and the goals of each stage remain the same across both frameworks.

Best Practices for Building a SANS-Based Incident Response Plan

So, how do you power up your SANS-based incident response plan and make sure it stands strong whether you’re defending a small manufacturing plant or a sprawling global OT network? Glad you asked. Here are tried-and-true best practices drawn from lessons learned across the industry.

Assemble an Expert, Empowered Incident Response Team

Your team is the engine driving the entire process. Start by putting together a diverse group of cybersecurity professionals—incident handlers, forensic analysts, network engineers, and communications leads. Make training and tabletop exercises a regular rhythm so skills stay sharp and everyone’s comfortable hitting “go” when an incident strikes.

More importantly, empower the team to take initiative when seconds matter. Clear roles, authority to act, and well-documented escalation paths help avoid confusion during high-pressure events.

Document and Update Step-by-Step Procedures

No firefighter runs into a burning building without a plan. Likewise, spell out your response procedures for each PICERL phase. This means detailed playbooks for containing ransomware, eradicating persistent threats, or restoring industrial control systems safely.

Keep these documents up to date with regular reviews. Lessons learned from post-incident debriefs and team feedback should feed directly back into your procedures. Agility beats bureaucracy every time.

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Map Out Your External Stakeholders

Incidents rarely respect organizational boundaries. Identify your key external contacts in advance: vendors, MSPs, forensic firms, law enforcement, regulators, and even industry ISACs. Capture their contact info and clarify when and how to involve each party, considering legal and contractual obligations as well as regulatory reporting windows.

That way, when the pressure’s on, you aren’t lost in a sea of business cards.

Build a Clear Communications Plan

Confusion is a common adversary during incident response. Establish a communication plan ahead of time—who needs to know what, when, and by whom. Make sure there are clear protocols for keeping executives, internal teams, and outside parties in the loop (and the press at bay, if needed).

Pre-approved messaging templates and designated company spokespeople ensure clear, controlled communication, minimize misinformation, and safeguard your organization’s reputation.

Invest in Advanced Threat Detection

The identification phase hinges on your ability to notice trouble fast. Lean on technologies like IDS/IPS, SIEM platforms, and behavioral analytics to spot suspicious activity early. Pair these tools with continuous log monitoring and regular tuning to address the relentless arms race between defenders and attackers.

And remember, tools are only useful if your team knows how to wield them effectively. Regular drills keep everyone on point.

Segment Your Network to Limit Damage

Compartmentalize critical systems and sensitive data so an attacker can’t waltz through your entire environment. Network segmentation helps contain incidents—think of it as shutting fire doors during a blaze. This not only limits the spread but simplifies incident investigation and recovery.

Dig into Root Cause Analysis

Don’t just extinguish fires—figure out why they started. Systematically analyze incidents using techniques like the five whys or fault tree analysis to uncover underlying weaknesses. This diligence is your ticket to implementing long-term fixes rather than band-aids.

Prioritize Trusted Recovery

When it’s time to bring systems back online, don’t rush. Validate backups, verify system integrity, patch known vulnerabilities, and test thoroughly before declaring victory. Only restore from sources you’re 100% confident are uncompromised—trust, but always verify.

Formalize Review and Reporting Processes

Your final obligation is to capture lessons learned. Establish structured processes for documenting investigative findings, reviewing incident response performance, and communicating insights to all relevant stakeholders.

Regularly scheduled reviews (along with ad hoc ones after major incidents) ensure you’re not just surviving cyberattacks—you’re getting stronger after each one.

Putting these best practices into play is what transforms an incident response plan from a paper exercise into a living, breathing workflow that stands up to real-world chaos.

Additional Learning: SANS Resources for Incident Response

If you’re eager to sharpen your skills or deepen your team’s expertise, SANS has you covered well beyond its frameworks. Their educational portfolio is impressively broad and practical:

  • In-depth blogs and white papers: SANS regularly publishes up-to-date articles and long-form guides on emerging threats, best practices, and technical deep dives—all freely accessible for practitioners at every stage.
  • Hands-on courses and certifications: SANS is renowned for its rigorous incident response training, complete with real-world labs and scenarios. Many professionals pursue SANS’s specialized courses, leading to respected GIAC certifications that cover everything from digital forensics to effective IR planning.
  • Graduate-level programs: For those looking to go the extra mile, SANS offers a Graduate Certificate in Incident Response, comprised of advanced coursework and culminating in valuable industry-recognized credentials.

Together, these resources empower security teams not just to understand incident response in theory, but to master it in practice—an essential step in building resilience for today’s OT environments.

NIST

A Deeper Dive: The Six Phases of Effective Incident Response

Let’s break down each phase, using the granular SANS model as our guide, to understand what it takes to succeed at every step.

Phase 1: Preparation

This is the most critical phase, as it lays the groundwork for everything else. Success here depends on a balanced focus on People, Process, and Technology.

  • Technology (The Right Tools): You need analysis tools capable of handling your environment’s data. But a tool is only “right” if your team is trained to use it and your processes allow for its effective deployment.
  • People (The Right Skills): Your team members must not only be trained on the tools but also understand their specific roles and responsibilities during a crisis. Do they have the necessary permissions (e.g., domain admin rights) or physical access required?
  • Process (The Right Plan): Your IR plan must define who gets involved and when. For example, your process should specify the exact criteria for waking up an executive at 2 a.m. for a critical incident.

Establish a Qualified Incident Response Team

A robust preparation phase starts with building a qualified incident response team. This isn’t just about assembling a group of technical experts; it means creating a multidisciplinary team, each member bringing a unique skill set to tackle complex security challenges. Ensure everyone on the team is equipped with up-to-date training and that their skills are regularly refreshed—cyber threats evolve, and so must your team.

Empowering your team is equally important. They should have the autonomy to make swift decisions when needed, backed by clear procedural guidelines. This combination of empowerment and structure ensures the team can respond rapidly and effectively, minimizing the impact of any incident.

 


 

Prevention is also a key part of preparation. NIST emphasizes conducting risk assessments, hardening network and host security, and continuous training. These preventative controls reduce the likelihood of an incident and provide valuable data sources if one occurs.

Prevention is also a key part of preparation. NIST emphasizes conducting risk assessments, hardening network and host security, and continuous training. These preventative controls reduce the likelihood of an incident and provide valuable data sources if one occurs.

Crafting an Effective Communications Plan

A solid communications plan is a vital supporting pillar of incident response. At its heart, the plan should ensure that information flows smoothly—internally and externally—during a high-pressure event. What should it cover?

  • Clear Notification Protocols: Outline exactly who needs to be informed in the event of an incident, and in what order. This includes escalation paths for alerting management, technical response teams, legal, HR, and any other relevant stakeholders.
  • Roles and Responsibilities: Specify who is authorized to communicate specific details, both within the organization and to outside parties. Define spokespersons for law enforcement, regulatory authorities (think: GDPR or HIPAA regulators), and, if necessary, the media.
  • Timing and Methods: Set standards for how quickly different groups should be notified, and what channels (email, phone, secure messaging) should be used for various types of updates. Speed and clarity are critical.
  • External Communications: Address how and when to contact vendors, partners, customers, and third parties like law enforcement or industry information-sharing organizations (e.g., ISACs). Make sure scripts or templates are developed in advance for initial notifications.
  • Consistency and Accuracy: Ensure that messages are vetted to maintain consistency, avoid speculation, and minimize replay risk. False moves here can erode trust.

Simply put, an incident response communications plan is your roadmap for “who says what, to whom, when, and how.” It prevents confusion, minimizes damage to your reputation, and supports a coordinated recovery.

Don’t Forget Your External Stakeholders

Preparation isn’t just about internal teams and technology—it’s also about knowing who outside your organization needs to be in the loop when something hits the fan. Think of all the external contacts that might play a crucial role: service providers, suppliers, law enforcement (hello, FBI or local police!), regulatory authorities, industry consortia, and yes—even the media.

Why bother mapping this out ahead of time? Because when an incident erupts, the last thing you want is to scramble for contact info or debate who should call whom. Documenting your external stakeholders—along with when and how you should engage them—ensures:

  • Coordinated, legally sound communications (no foot-in-mouth moments with the press or regulators)
  • Swift support from partners or vendors (like your managed security services provider)
  • Compliance with any industry or contractual notification requirements
  • Stronger relationships with third parties, leading to faster recovery and reduced confusion

Include up-to-date contact details and guidance on engagement for each, and revisit this list regularly—it’s amazing how quickly org charts and email addresses can change.

Phase 2: Identification (Detection & Analysis)

Key Metric: Mean Time to Detection (MTTD) – The time from when an attacker acts to when you detect it.

Once an incident begins, the goal is to find it quickly. Success requires:

  • Understanding Attack Vectors: Know the general threats (common malware, phishing) and the specific vectors tailored to your organization (e.g., exposed high-risk protocols required for business).
  • Identifying Indicators: Based on attack vectors, what indicators of compromise (IOCs) should you be looking for in your logs and alerts?
  • Structured Triage: Develop a clear process to distinguish a benign event from a true incident and know when and how to escalate it. Not all incidents are equal—a compromised domain controller is far more urgent than a series of failed login attempts from an external IP.

Implementing Advanced Detection Capabilities

Speed and accuracy in the Identification phase depend on modern, multilayered detection capabilities—not just good luck or a hunch. So, how do you get there?

  • Deploy the Right Detection Tools: Rely on solutions built for scale and complexity. Intrusion Detection Systems (IDS), Security Information and Event Management (SIEM) platforms (think Splunk or IBM QRadar), and advanced threat protection suites are your best friends here. These tools correlate data, analyze patterns, and surface anomalies across vast data sets, helping you spot trouble faster than you could manually.

  • Automate Where Possible: The best detection setups automatically sift through millions of events, flagging only true threats for human review. This reduces alert fatigue and enables your team to keep pace with attackers.

  • Regularly Update, Tune, and Test: Detection is not a “set it and forget it” discipline. Keep your signatures, detection rules, and analytic models up to date. Routinely test your alerts against emerging threat techniques, so your team isn’t blindsided by new TTPs (Tactics, Techniques, and Procedures).

  • Balance Technology with Human Insight: Even the shiniest tool requires skilled analysts behind the scenes. Pair regular training with the latest detection playbooks so your team can effectively investigate and act on alerts.

Done right, advanced detection shrinks the Mean Time to Detection (MTTD) and gives you a fighting chance to contain threats before they snowball.

Phase 3, 4, & 5: Containment, Eradication, and Recovery

Key Metric: Mean Time to Response (MTTR) – The time from the initial detection to full recovery.

This is where the active “response” takes place.

  1. Containment: The immediate goal is to stop the bleeding. This involves isolating the affected systems to prevent further damage. This might mean taking a server offline, implementing restrictive firewall rules, or disabling user accounts. Sometimes, containment efforts uncover new aspects of the attack, sending you back to the Identification phase.

The Role of Network Segmentation in Containment

Network segmentation is a strategic powerhouse for effective containment. By dividing your network into discrete, well-defined zones, you essentially build firebreaks—limiting an attacker’s ability to move laterally. This means that if malware or an intruder breaches one area, it can’t easily pivot to more sensitive systems or critical data elsewhere.

For example, segmenting finance systems apart from user workstations or R&D resources ensures that a breach in one domain isn’t an express ticket to the company’s crown jewels. This not only slows down attackers and reduces potential damage, but it also simplifies your team’s job during a crisis. With clearly partitioned environments, incident responders can focus their containment efforts more precisely—quarantining only the affected segments instead of dragging the entire enterprise into lockdown.

Network segmentation, then, isn’t just “nice to have”—it’s a key defensive layer that gives your organization time and breathing room to respond before things snowball.
2. Eradication: Once contained, you must remove the threat from your environment. This could involve deleting malware, patching vulnerabilities, or even rebuilding systems from a known-good state. It’s crucial to be thorough, as sophisticated attackers often leave multiple backdoors.
3. Recovery: The final step is to restore the affected systems and bring business operations back to normal in a safe and timely manner.

What Does Trusted Recovery Involve?

Trusted recovery is the linchpin of an effective recovery phase. But what does that actually mean in practice? At its core, trusted recovery is about ensuring that all restored systems and applications are truly free from compromise—so you’re not just putting Humpty Dumpty back together, but making sure he’s not full of cracks.

Here’s what trusted recovery typically requires:

  • Restoring from Clean Backups: Always use backups that you’ve verified as uncontaminated—otherwise, you risk reintroducing malware straight back into production.
  • Applying Critical Patches: Take this opportunity to close any vulnerabilities that may have been exploited. If the root cause was an unpatched system, now’s the time to fix it.
  • Integrity Verification: Before turning restored systems loose, verify the integrity of software, system files, and data. Use cryptographic checksums or file integrity monitoring tools to confirm nothing has been tampered with.
  • Rigorous Testing: Don’t just power things up and hope for the best. Run validation tests to confirm everything is functioning as expected—and securely.

By following these steps, you maintain confidence in your operations and ensure that when business resumes, it does so on solid ground.

Why Root Cause Analysis Matters in Incident Response

Stopping the symptoms of an attack isn’t enough—you also need to ensure it can’t happen again. That’s where root cause analysis comes into play.

Root cause analysis is all about digging beneath the surface to uncover how and why the breach occurred in the first place. Was it a misconfigured firewall, an unpatched vulnerability, a successful phishing email, or a process gap? Pinpointing the true culprit lets you address foundational weaknesses rather than just cleaning up after the fact.

A methodical approach is essential here. Techniques like the “Five Whys,” Ishikawa (fishbone) diagrams, and fault tree analysis are often used to systematically peel back the layers of contributing factors. These aren’t just academic exercises—they help eliminate guesswork and ensure fixes are robust, targeted, and sustainable.

By investing the time to get to the heart of the issue, you’re not just closing a single incident—you’re fortifying your entire security posture against repeat performances.

Phase 6: Lessons Learned (Post-Incident Activity)

The incident isn’t over when the systems are back online. This final phase is essential for maturing your security program.

  • Conduct Fair and Honest Reviews: Analyze the performance of your people, processes, and technology without placing blame.
  • Celebrate Strengths & Identify Weaknesses: What worked well? Pat those teams on the back. Where were the bottlenecks or missed opportunities? Acknowledge them honestly.
  • Develop an Actionable Plan: Don’t just document your findings in a report that gathers dust. Create a plan of action with assigned owners and deadlines to implement the lessons you’ve learned.
  • Document Everything: Proper documentation is crucial for compliance (e.g., SOC 2), future correlation, and demonstrating program maturity. Consult with legal and policy teams to understand evidence retention requirements.

A structured approach to this phase goes beyond a one-off postmortem. Establish clear guidelines for gathering evidence, analyzing data, and documenting findings so they’re useful and actionable—not just for the current incident, but for the next one. Make sure your process includes:

  • Stakeholder Reporting: Ensure your findings reach all relevant stakeholders—decision-makers, technical teams, and anyone accountable for follow-up actions. Good communication here leads to faster, more effective responses in the future.
  • Routine Reviews and Triggers: Define how often reviews should take place and what kinds of incidents warrant a deeper dive. This keeps your process adaptable and ensures you don’t miss emerging threats or recurring issues.
  • Continuous Improvement: Use what you’ve learned to update playbooks, refine detection rules, and train staff. The true value of this phase is in using real-world experience to strengthen your overall security posture.

By making post-incident activity a well-defined, repeatable process, you transform “lessons learned” from a checkbox exercise into a cornerstone of organizational resilience.

Conclusion: Building a Resilient Security Program

Both the NIST and SANS frameworks provide a proven roadmap for handling security incidents. By understanding and implementing these phases—from proactive preparation to diligent lessons learned—you can move from a reactive state of chaos to a structured, efficient, and constantly improving incident response program. This structure not only minimizes the impact of an attack but also builds a stronger, more resilient organization over time.

Need help building or refining your incident response plan? The experts at Insane Cyber are here to help. Contact us today to learn how we can strengthen your security posture.

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