Threat Hunter - Senior - EY GDS Spain - Hybrid
Cyber Security – Senior Threat Hunter

The opportunity:
We are looking for SOC L3 Threat Hunter is responsible for proactively identifying advanced, stealthy, andpreviously unknown threats across enterprise environments. This role operates beyond alert-driven SOCoperations, focusing on hypothesis-based threat hunting, adversary behaviour analysis, and closingdetection gaps across Microsoft Sentinel, Microsoft Defender for Endpoint, and Defender for IoT.

The role serves as a technical authority within the SOC, supporting L1/L2 analysts, partnering with Incident.Response and Detection Engineering teams, and continuously improving the organization’s threat visibility and SOC maturity.

Your key responsibilities:

Conduct hypothesis-driven, TTP-centric threat hunts using telemetry from Microsoft
Sentinel and Microsoft Defender platforms.

Develop hunt hypotheses based on:

Adversary campaigns

Observed environmental weaknesses

Hunt for advanced attack behaviors.

Validate findings with evidence and determine impact before escalation.





Perform advanced KQL-based threat hunting across large data volumes in Microsoft
Sentinel.

Identify detection blind spots, noisy analytics, and data quality issues.

Conduct advanced endpoint hunting using Defender Advanced Hunting

Correlate endpoint telemetry with SIEM data to reconstruct end-to-end kill chains.

Perform threat hunting across IoT/OT and ICs environments using Microsoft Defender
for IoT telemetry where applicable

Produce formal threat hunt reports detailing: Hunt Hypothesis, Data Sources, Findings
and evidence, MITRE ATT&CK; mapping and recommended remediation

Skills and attributes for success:

4–7+ years in SOC, Threat Hunting, Incident Response, or Detection Engineering.

Proven experience performing proactive threat hunting (not tool monitoring).

Experience working in enterprise-scale SIEM and EDR environments.

Advanced expertise in MS Sentinel and Defender Suites

📌 Threat Hunter (Madrid)
🏢 Ey Studionederland
📍 Madrid