Your EDR and MDR are doing their job. The rest of your attack surface is uncovered.

Your EDR and MDR are doing their job. The rest of your attack surface is uncovered.

About Author

Kristian Wright

Kristian Wright is CEO and co-founder of enhanced.io, a channel-only SOC-as-a-Service provider built for MSPs. He has over 30 years in IT leadership and has co-founded three service delivery businesses.

enhanced.io, the channel-only Open XDR SOCaaS for MSPs

Endpoint Detection and Response watches what happens on a managed device. Processes, files, registry changes, memory injection. It does that well. 

Managed Detection and Response builds on EDR. It adds a SOC team that triages alerts and responds to incidents. The analysts make endpoint detection faster and more accurate. They only see what the agent records. 

The problem is what sits outside the device. Network traffic between hosts. Identity systems like Microsoft 365 and Entra ID. Cloud workloads in AWS and Azure. Third-party SaaS apps holding your client data. A growing population of IoT and OT equipment that cannot run an agent at all. None of it appears on the endpoint console. 

EDR was never built to cover that ground. Neither was MDR. They protect the device. The rest of the attack surface needs different telemetry. 

The five blind spots EDR and MDR were never designed to cover 

1. Network blind spots 

EDR watches its own host. It does not watch the path between hosts. 

Lateral movement, command and control beaconing, DNS tunnelling and bulk data exfiltration travel across the network. An attacker who pivots from one device to another, or from a compromised cloud workload to a database, moves through traffic an agent will never see. The endpoint console shows nothing because nothing happened on the endpoint. 

Network Detection and Response (NDR) closes the gap. It analyses flows, protocols and anomalous behaviour at the wire level and surfaces what endpoint telemetry misses. 

2. Identity blind spots 

Most modern intrusions start with a credential, not a process. 

M365 account takeovers, OAuth consent phishing, session token theft and privilege escalation inside Entra ID happen entirely in identity systems. The attacker never touches a managed device. They sign in with stolen credentials or a stolen token from their own laptop, then operate inside Microsoft 365, SharePoint, Teams and connected SaaS apps. The legitimate user notices nothing. The endpoint sees nothing. 

Identity Threat Detection and Response (ITDR) ingests sign-in logs, MFA events and conditional access decisions. It catches what the endpoint console will never see. 

3. Cloud blind spots 

Workloads, configurations and APIs sit outside agent coverage. 

Misconfigured IAM roles, exposed S3 buckets, unrotated access keys, public-facing APIs and shadow cloud subscriptions all create entry points that endpoint agents do not monitor. An attacker who finds a misconfigured admin role in AWS does not need to touch a single managed laptop. They operate inside the cloud control plane. 

Cloud Security Posture Management (CSPM) and cloud workload telemetry surface these gaps. Without them, an attacker pivots through your client estate for weeks before anyone notices. 

4. SaaS blind spots 

Third-party SaaS apps now hold more sensitive data than endpoints do. 

Malicious OAuth grants, over-permissioned app integrations and compromised third-party vendors give attackers a direct path to client data without ever touching a device. The path runs through app-to-app permissions inside Microsoft 365, Google Workspace, Salesforce and dozens of other platforms an MSP client uses every day. 

SaaS Security Posture Management (SSPM) and OAuth audit telemetry catch app-to-app abuse and unauthorised data access in the place where the attacker is actually operating. 

5. IoT and OT blind spots 

Some devices were never designed to host an agent at all. 

Network cameras, printers, building management systems, smart sensors, programmable logic controllers, medical devices and BYOD hardware do not run endpoint software. Their firmware does not allow it. In a typical SMB estate, this category is growing faster than the managed device population. 

Network-level telemetry is the only way to see these devices. Without it, every printer and every smart thermostat is invisible to your security stack. Attackers know this. The 2024 Microsoft Digital Defense Report found that over 90% of ransomware attacks reaching the encryption stage used unmanaged devices as the initial access point or for remote encryption. 

A common breach scenario your EDR and MDR will not see 

A finance user at one of your clients clicks a phishing link in a Teams message. The page looks like a legitimate Microsoft sign-in. They enter their credentials and approve the MFA prompt. The attacker now holds a valid M365 session token. 

The attacker signs in from a new IP in another country. Conditional access rules are not strict enough to block the login. They access SharePoint, exfiltrate 12 GB of client files, and create an inbox forwarding rule on the user mailbox so future correspondence gets copied to an external address. 

The endpoint agent on the finance user laptop sees nothing. No malicious process. No file write. No memory injection. No signature match. The agent has nothing to report because nothing malicious happened on the device. The MDR SOC team sees nothing either, because they only investigate what the agent flags. 

Open XDR catches this because it correlates three events into one incident. The identity event (sign-in from a new geography), the cloud event (bulk SharePoint download), and the SaaS event (new mail forwarding rule). An analyst sees the pattern within minutes. Your client gets a call before the data leaves the estate. 

Side-by-side coverage. EDR, MDR and Open XDR. 

A coverage map for the most common attack vectors MSP clients face today. EDR and MDR share the same data layer, so their coverage is identical for these attack types. Open XDR adds telemetry from network, identity, cloud and SaaS so it sees the rest. 

Attack vector 

EDR 

MDR

Open XDR 

Malicious processes on a managed device 

Yes 

Yes 

Yes 

File-based malware 

Yes 

Yes 

Yes 

Memory injection 

Yes 

Yes 

Yes 

Ransomware encryption on the endpoint 

Partial 

Partial 

Yes 

Lateral movement between devices 

Partial 

Partial 

Yes 

Command and control beaconing 

No 

No 

Yes 

Data exfiltration over the network 

No 

No 

Yes 

M365 account takeover 

No 

No 

Yes 

OAuth consent phishing 

No 

No 

Yes 

Session token theft 

No 

No 

Yes 

Cloud misconfiguration in AWS or Azure 

No 

No 

Yes 

Public-facing API abuse 

No 

No 

Yes 

Shadow SaaS subscriptions 

No 

No 

Yes 

IoT and OT device compromise 

No 

No 

Yes 

Printer or camera used as a pivot point 

No 

No 

Yes 

Cross-domain attack correlation 

No 

No 

Yes 

A note on fairness: This compares standard EDR and MDR deployments. Some MDR providers have added identity (ITDR) or cloud (CSPM) modules to their core service. Where they have, treat those rows as Partial for that provider. The default architecture of MDR remains endpoint-first. 

Is enhanced.io a fit for your MSP? 

Book a 30-minute call with Hannah, our co-founder. We talk through your MSP, your current security setup and where you want to take it. If enhanced.io is a fit, we tell you. If not, we tell you that too. 

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Beyond the endpoint: The evolution of MSP security

FAQ

Why is endpoint security not enough on its own?

Endpoint Detection and Response watches managed devices. It does not see network traffic between devices, identity events in Microsoft 365 or Google Workspace, cloud workload activity, SaaS configurations, or any device that does not run an agent. Managed Detection and Response uses the same telemetry, so it has the same blind spots. Most modern attacks happen in those categories. An endpoint-only strategy leaves most of the attack surface uncovered.

What attacks bypass endpoint agents entirely?

Session token theft, OAuth consent phishing, M365 account takeovers, cloud misconfiguration exploits, OAuth-based data exfiltration from SaaS apps, attacks against IoT and OT devices that do not run agents, and pivot attacks through printers, cameras and unmanaged network gear. None of these touch a managed endpoint.

If we already have MDR, are we covered?

Not for these blind spots. MDR is EDR with a SOC team layered on top. The analysts add human triage and faster response, but they only see what the agent records. If the endpoint does not capture an M365 sign-in or a cloud configuration change, the MDR analyst has nothing to investigate. Some MDR providers have started adding identity or cloud modules to their service. Where they have, those gaps narrow. The default architecture of MDR remains endpoint-first. Open XDR was built to ingest all five telemetry layers from the start: network, identity, cloud, SaaS and endpoint.

Do EDR and MDR detect lateral movement between devices?

Only partially. The agent sees its own host. It detects outbound connections from that host and inbound connections to it. It does not see traffic between two other hosts, or traffic to and from an unmanaged device. MDR adds a SOC team to triage what the agent flags, but the team only sees what the agent records. Network Detection and Response covers that gap by analysing flows at the wire level.

Do EDR and MDR see a Microsoft 365 account takeover?

No. M365 sign-ins happen on Microsoft servers, not on the endpoint. An attacker with a valid token signs in from their own machine, accesses SharePoint, downloads files and creates inbox rules. The endpoint agent on the legitimate user laptop sees nothing because nothing happens on it. MDR analysts only see what the agent captures, so they also see nothing. Identity Threat Detection and Response is the layer that catches this.

What is an agentless device and why does it matter for MSP security?

An agentless device is a piece of hardware that does not host endpoint security software. Printers, network cameras, smart sensors, programmable logic controllers, building management systems, medical devices and most IoT equipment fall in this category. Their firmware does not allow agent installation. In a typical MSP client estate, agentless devices outnumber managed ones. Without network-level telemetry, they are invisible to the security stack.

How does Open XDR cover what EDR and MDR miss?

Open XDR ingests telemetry from network sensors, identity systems, cloud platforms, SaaS apps and endpoint agents into one platform. It correlates events across all five layers and surfaces incidents that would be invisible to any single tool. A 24/7 SOC team triages alerts and responds. The result is full visibility of the attack surface instead of a device-only view.

What is the difference between EDR, MDR, XDR and Open XDR?

What percentage of breaches start outside the endpoint?

What is the difference between EDR, MDR, XDR and Open XDR?

What percentage of breaches start outside the endpoint?