Key takeaway
Managed EDR for Microsoft Defender adds 24/7 SOC investigation, ZeroDwell containment and included breach-response support to existing Defender telemetry.
Managed security for Microsoft Defender
On March 4, 2026, Xcitium introduced Managed EDR for organizations using Microsoft Defender that need stronger protection and ongoing operational ownership. The service complements existing Defender Antivirus and Defender for Endpoint deployments rather than replacing them, adding ZeroDwell containment, continuous SOC oversight and incident response.
Containment of unknown files
In Xcitium’s ZeroDwell architecture, unknown files run in a virtualized environment without interacting with production systems while their behavior is analyzed in real time. The company says this kernel-level containment is designed to reduce execution risk without changing an existing Defender deployment.
24/7 SOC ownership and response
Xcitium’s human-led SOC monitors Defender telemetry around the clock, validates alerts and investigates suspicious activity. During an incident, containment can begin immediately and remediation can continue through resolution; the company says this ownership is consistent at any hour.
Breach response is included
In its March 2026 announcement, Xcitium included breach response in Managed EDR. The company said the announced offer allowed response to begin without a separate retainer, emergency contract or usage-based charge. The model was intended to reduce procurement and contract delays during a crisis.
Executive perspective and existing tools
Xcitium VP of Global Security Services and Solutions Bill Barry said Microsoft Defender provides visibility into threats, but visibility alone does not stop attacks. Managed EDR is designed to add continuous SOC ownership and containment while preserving an organization’s Microsoft security investment; Xcitium says infrastructure changes are not required.
Availability
Xcitium said the service was immediately available in March 2026; organizations can request a demonstration and review its fit for their Microsoft Defender environment.