How to Operationalize CTEM With Microsoft Security Tools

The pressing question for cybersecurity professionals today is not if your organization has exposure. It’s how quickly you can identify, validate, and reduce it. That’s where Continuous Threat Exposure Management (CTEM) comes in.  CTEM is a proactive, continuous approach to managing cyber risk by simulating, validating, and prioritizing real-world attack paths. It replaces point-in-time assessments with an ongoing, risk-based method that helps security leaders allocate resources based on verified exposure and business impact. 

CTEM aligns with modern enterprise needs, shifting from reactive protection to preemptive resilience, and Microsoft Security is uniquely positioned to help organizations operationalize CTEM at scale. 

Microsoft Security + CTEM: A Framework Alignment 

Microsoft’s integrated security ecosystem delivers end-to-end visibility and control across the CTEM lifecycle by unifying identity, endpoint, cloud, and data telemetry under a single, scalable platform.  Tools like Microsoft Defender, Entra ID, Purview, and Sentinel can be holistically mapped to create a robust CTEM program and, work in concert to surface exposures, correlate threats, validate controls, and prioritize remediation based on real-world risk.  

1. Redefine Your Discovery Process Using Microsoft Purview

Discovery is the cornerstone of Continuous Threat Exposure Management (CTEM), and it starts with knowing what truly matters. This means identifying high-value assets, sensitive data, privileged identities, and critical business processes. These are all elements that, if compromised, could significantly impact operations, regulatory compliance, or organizational reputation. 

Microsoft Purview empowers security teams to redefine this discovery process by delivering unified visibility across cloud, on-premises, and hybrid environments. Acting as a centralized source of truth, Purview enables organizations to discover, classify, and contextualize data, devices, and identities. 

By integrating Microsoft Purview into your CTEM strategy, you gain actionable insights into your risk surface, transforming discovery from a static inventory exercise into a dynamic, business-aligned capability. 

Example: A healthcare organization uses Purview to identify and tag sensitive patient data across SharePoint, Exchange, and Azure storage. This scoping step informs downstream threat simulations focused on regulated data exfiltration paths. 

2. Detect: Map the Full Threat Landscape With Microsoft Defender

After identifying critical business priorities and critical assets in discovery, the detection phase begins. This is where all likely exposure areas utilized by the attacker in penetrating the critical assets are identified. 

The detection phase goes beyond the scanning model. A multi-layer approach to detection is required which integrates real-time protection with deep threat correlation in platforms.  

Microsoft Defender and Microsoft Sentinel team up in offering this: the former raises active threats and exploitable entry points; the latter draws the threads together at the level of the attack surface to show broader patterns and data sensitivity to elevate the most urgent risks. 

Microsoft Defender delivers comprehensive, multi-layered detection across your entire digital estate, covering endpoint, identity, and external attack surfaces in a single, integrated solution: 

• Defender for Endpoint continuously monitors devices for known vulnerabilities, insecure configurations, exploitation attempts, and lateral movement activity, allowing security teams to block threats before they escalate. 

• Defender for Identity protects hybrid identity environments by monitoring on-premises Active Directory for suspicious authentication behaviors, exposed credentials, and privilege escalation paths. 

• Defender External Attack Surface Management (EASM) uncovers unmanaged or unknown internet-facing assets, such as shadow IT domains, IPs, cloud services, and APIs, providing visibility into your organization’s full external footprint. 

Microsoft Sentinel acts as the central nervous system, ingesting telemetry from all Defender tools and more. It correlates signals from endpoints, identities, cloud infrastructure, SaaS apps, and networks using analytics, threat intelligence, and MITRE ATT&CK mapping. This enables security teams to detect attack paths early, reduce noise, and respond with precision. 

Together, Defender and Sentinel create a powerful detection engine: one that not only blocks real-time threats but also correlates signals across your environment to uncover stealthy attacks and emerging risks. 

Example: A global manufacturer uses Defender EASM to discover previously unknown exposed APIs. Sentinel correlates activity from those APIs with anomalous sign-in patterns, prompting immediate remediation to prevent a potential breach. 

3. Prioritize: Focus on What’s Real with Microsoft Defender, Sentinel, and Purview

Discovery alone can flood security teams with exposure data, vulnerabilities, misconfigurations, suspicious behaviors, but not all findings are equal. The prioritization phase of CTEM helps teams zero in on what truly matters: exposures that are exploitable, business-critical, and likely to be targeted. 

Microsoft’s integrated security tools combine threat intelligence, contextual scoring, and data sensitivity to elevate the most urgent risks. 

• Microsoft Defender surfaces real-time threat intelligence and analytics on active exploitation, enabling teams to understand which vulnerabilities are being targeted in the wild and should be remediated first. 

• Microsoft Sentinel ingests and correlates signals across your entire environment—endpoints, identities, email, cloud workloads, and beyond. It applies correlation rules, machine learning, and MITRE ATT&CK mapping to link seemingly isolated alerts into high-fidelity incidents that reflect real attack chains. 

• Microsoft Purview adds data sensitivity context to the mix. By classifying and labeling regulated or critical business data, Purview helps security teams understand the true impact of exposure, prioritizing remediation efforts based on where sensitive information lives and how it could be accessed. 

By integrating insights from across Defender, Sentinel, and Purview, Microsoft helps organizations shift from a long list of technical issues to a short list of validated, business-aligned risks, ensuring limited time and resources are focused where they’ll make the biggest impact. 

Example: Sentinel detects a spike in credential phishing attempts targeting senior executives. Purview confirms that the affected accounts have access to sensitive IP and financial data. Combined with Entra’s high-risk sign-in alerts, the SOC rapidly implements phishing-resistant MFA and adaptive access controls for execs. 

4. Validation: Prove What’s Real with Microsoft Defender TI and Sentinel Hunting

Identifying and prioritizing exposures is crucial, but validation turns theory into fact. In this phase of CTEM, security teams simulate real-world attack paths to confirm whether exposures are truly exploitable and whether current defenses can stop them in time. 

This isn’t guesswork. Validation uses live intelligence and active threat hunting to answer two key questions: Can attackers reach critical assets? And if they do, will we catch and contain them? 

• Microsoft Defender Threat Intelligence (Defender TI) delivers the latest adversary TTPs, sourced from active threat actor campaigns worldwide. Security teams use this intelligence to design realistic attack simulations that reflect how real-world adversaries operate. These TTPs integrate with red and purple team platforms to safely emulate attacker behavior against your environment. 

• Microsoft Sentinel Hunting empowers analysts to actively validate exposures using structured queries and threat hunting techniques mapped to the MITRE ATT&CK framework. Hunters can test whether prioritized attack paths are detectable in real time, whether alerts fire as expected, and whether automated playbooks activate the correct response. 

Together, Defender TI and Sentinel Hunting give security leaders confidence that what they’ve prioritized is not only real, but actively exploitable and urgent. And if something slips through, they’ll know exactly where to tune controls. 

Example: An energy company uses Defender TI to simulate lateral movement from a low-privileged account. Sentinel Hunting queries validate that the path is detectable, and alerts escalate properly before the attacker can reach SCADA systems. 

5. Enroll: Operationalize Response with Microsoft Defender and Purview

Once exposures are identified, validated, and prioritized, the next challenge is scale, turning insight into action across people, processes, and technology. That’s the purpose of the Enroll phase: embedding CTEM into daily operations so that exposure management becomes a repeatable, business-wide function.  

This phase is about operational maturity. It’s not just about enabling tools; it’s about enabling teams. Microsoft Defender and Microsoft Purview work together to automate containment, streamline vulnerability management, and enforce compliance with minimal manual effort. 

• Microsoft Defender standardizes posture management across your organization. It applies security baselines consistently across cloud environments, business units, and resource types, with built-in automation to patch vulnerabilities and flag deviations from policy. 

• Microsoft Purview enforces governance by embedding data protection into everyday workflows. It applies consistent classification, loss prevention, and compliance rules across Microsoft 365, Azure, and multicloud services, ensuring that sensitive data stays protected without slowing down the business. 

Crucially, this phase also brings in business stakeholders. With integrated dashboards and reporting, security leaders can demonstrate how CTEM is actively reducing risk, supporting compliance, and improving operational resilience. 

Example: A financial services firm detects anomalous file access by a user traveling overseas. Defender automatically blocks the threat, Purview logs the access event for compliance tracking, and Sentinel escalates the incident, all without manual intervention. 

6. Test: Measure, Refine, and Prove Resilience Over Time With Microsoft Defender and Sentinel

The Test phase closes the CTEM loop, shifting exposure management from implementation to continuous improvement. It’s where security teams validate that their controls don’t just exist but work under real-world conditions. This phase focuses on system-wide validation. It asks: Are we effectively preventing, detecting, and responding to today’s most relevant threats? And can we prove it? 

• Microsoft Defender Attack Simulation lets organizations simulate real-world threat scenarios using up-to-date attacker techniques, tactics, and procedures (TTPs). These simulations mimic the paths threat actors use in the wild testing how well your environment detects, contains, and responds across cloud, identity, and endpoint layers. 

• Microsoft Sentinel Red Teaming empowers analysts to run purple team exercises and adversary emulations using the MITRE ATT&CK framework. These tests evaluate whether detection rules, analytics, and automated playbooks trigger as expected, providing evidence that your detection strategy is working or highlighting where it’s not. 

With Defender and Sentinel working in tandem, the Test phase becomes more than just a check-the-box exercise, it’s a rigorous performance feedback loop that drives tuning, automation, and resilience. 

Example: A financial institution uses Microsoft Defender Attack Simulation to launch phishing and lateral movement emulations. Sentinel Red Teaming maps the activity to the kill chain and validates that detections, escalations, and playbooks trigger appropriately. The findings lead to alert refinements and staff training enhancements. 

Operationalize CTEM With Ascent Solutions and Microsoft Security 

Microsoft Security is uniquely positioned to help operationalize CTEM across the full lifecycle, from discovery and prioritization to validation, enrollment, and testing. With a unified, intelligence-driven ecosystem that spans identity, endpoint, data, cloud, and SIEM/XDR, Microsoft enables security teams to shift from reactive defense to proactive resilience at scale.  

Microsoft Security provides the tools. Ascent Solutions brings the strategy. Our deep expertise in Microsoft Security helps you design and operationalize CTEM for your organization, translating product capabilities into measurable security outcomes. The result? Better visibility. Smarter prioritization. Faster response. Measurable risk reduction. If you’re ready to move beyond static assessments and fragmented tools, it’s time to put CTEM into action with a partner built for end-to-end exposure management.  

From discovery to testing, we help you create a CTEM strategy that fits your business and helps you to get the most from your Microsoft investment. Contact us today.