Cyber Defense Analyst III

Chicago Mercantile Exchange•Chicago, IL

About The Position

The Cyber Defense Engineer III position is responsible for monitoring, detecting, and validating complex security threats. As our Security Operations Center transitions toward an engineering and automation-first model, this role acts as a critical bridge between traditional cyber defense monitoring and modern development practices. You will take a leading role in deep-dive telemetry analysis while dedicating significant time to identifying process bottlenecks, developing automation scripts, and integrating security telemetry into our SOAR platforms. This position is ideal for candidates looking to evolve their career by applying an engineering mindset to everyday monitoring challenges, helping us eliminate manual toil, improve detection fidelity, and support the deployment of AI-augmented triage workflows.

Requirements

4–6 years of dedicated experience in a Security Operations Center (SOC), Detection Engineering, or advanced Cyber Defense monitoring environment.
Deep knowledge of network protocols, operating system internals (Windows/Linux/macOS), and adversary tactics mapped to the MITRE ATT&CK framework.
Practical proficiency in Python or PowerShell, specifically for interacting with REST APIs, parsing JSON/XML, and automating daily security monitoring tasks.
Hands-on experience building, maintaining, or modifying playbooks within modern SOAR platforms (e.g., Cortex XSOAR, Splunk SOAR, Torq, or Tines).
Familiarity with cloud environments (preferably GCP or AWS) and investigating cloud-specific telemetry and identity abuse.
Experience or strong interest in modern engineering practices, including version control (Git), Detection-as-Code, and basic CI/CD workflows.
Willingness to learn and adapt to emerging AI capabilities, including testing and refining LLM prompts for security investigations.
Strong analytical and problem-solving mindset; naturally curious about how things work and how to make them more efficient.
Excellent communication skills, capable of translating complex telemetry into clear, actionable summaries for Incident Response and engineering peers.
Highly self-directed, able to balance active alert analysis with long-term automation and playbook development projects.
Collaborative team player who enjoys mentoring peers and bridging the gap between monitoring operations and development teams.
BA/BS in Computer Science, Information Security, Engineering, or related field (non-tech degrees acceptable with appropriate levels of Information Security job experience and/or certifications).
Relevant industry certifications strongly preferred: SANS GCIA, GCFA, GCDA, or practical automation/cloud certs (e.g., SEC573, AWS/GCP Security).

Responsibilities

Perform deep-dive analysis and validation of complex security events across network, host, identity, and cloud (GCP) telemetry to accurately identify malicious activity and reduce false positives.
Ensure seamless handoffs to the Incident Response team by providing highly contextualized, enriched, and validated security alerts.
Proactively identify manual, repetitive monitoring tasks within the SOC and write Python scripts or build SOAR playbooks to automate them.
Support our transition to Detection-as-Code (DaC) by developing, testing, tuning, and deploying SIEM detection rules using version control (Git) and CI/CD pipelines.
Partner with our global engineering and automation teams to test, validate, and refine new AI-assisted workflows and agentic triage outputs to ensure high operational accuracy in our monitoring ecosystem.
Conduct proactive, hypothesis-driven threat hunts and operationalize threat intelligence into new, automated detection mechanisms.
Provide technical mentorship to junior monitoring analysts, fostering a culture of continuous learning, critical thinking, and automation within the SOC.
Maintain detailed documentation of monitoring processes, playbook logic, and detection schemas within the Knowledge Management System.