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Level 3 End User Security Engineer (Microsoft Defender for Endpoint)

InnoCore Solutions, Inc.Dallas, TX🇺🇸United StatesPosted 4 Sept 2026

Quick Overview

Seniority
Mid Senior
Work mode
Hybrid
Location
Dallas, TX, United States
Posted
7 hours ago

Job Description

We are looking for a highly skilled Level 3 End User Security Engineer responsible for administering, troubleshooting, monitoring, and enhancing endpoint security using Microsoft Defender for Endpoint (MDE). This role will serve as a senior escalation point for complex endpoint security incidents and will work closely with Security Operations, Infrastructure, Identity, and End User Computing teams.

Responsibilities:

  • Serve as the Level 3 escalation point for complex endpoint security incidents, problems, and vulnerabilities.
  • Administer, monitor, and optimize Microsoft Defender for Endpoint (MDE) across enterprise Windows endpoints.
  • Investigate and respond to malware, ransomware, phishing, suspicious processes, credential theft, and other endpoint security threats.
  • Perform advanced threat hunting and incident investigation using Microsoft Defender Advanced Hunting and KQL.
  • Analyze endpoint timelines, process trees, command-line activity, file/registry changes, network connections, and other security telemetry.
  • Perform endpoint containment and remediation activities, including device isolation, antivirus scans, Live Response, and remote remediation.
  • Develop KQL queries, custom detections, dashboards, and threat-hunting queries to identify suspicious activity across the enterprise.
  • Participate in security incident response, vulnerability remediation, security projects, and continuous improvement initiatives.
  • Maintain appropriate documentation, audit trails, metrics, and reporting for endpoint security operations.

Requirements:

  • 5+ years of experience in endpoint security, Windows security, cybersecurity, or related IT infrastructure roles.
  • 3+ years of hands-on experience with Microsoft Defender for Endpoint (MDE) in a medium-to-large enterprise environment.
  • Ability to develop KQL queries for threat hunting, investigation, detection, and security analytics.
  • Experience working in an L3 escalation/support environment and independently resolving complex technical issues.
  • Strong understanding of security incident response processes and evidence preservation.
  • Excellent troubleshooting, analytical, communication, documentation, and problem-solving skills.

Education:

  • Bachelor's degree in Information Technology, Computer Science, Cybersecurity, Engineering or a related field.

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