Open to opportunities

Justin Castillo

@justincastillo

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Aspiring security analyst with hands-on experience in threat detection.

United States

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What I'm looking for

I seek a dynamic role in cybersecurity where I can apply my skills in threat detection and incident response, contributing to a proactive security posture within an organization.

I am a dedicated and passionate security analyst in training, currently pursuing my Master of Science in Information Security. With certifications in CompTIA Security+, Network+, A+, and AWS Cloud Practitioner, I have developed a solid foundation in cybersecurity principles and practices. My hands-on experience includes working in a home SOC lab where I deployed Azure VMs and utilized Microsoft Sentinel to enhance incident response capabilities.

Throughout my training, I have demonstrated my ability to triage alerts, investigate network traffic, and document incidents with precision. I have successfully reduced false positives by 30% through tuning analytic rules and have created Python scripts to enrich incident investigations. My commitment to continuous learning is evident through my completion of the TryHackMe Security Analyst Level 1 Path, where I achieved a 95% score and practiced essential skills in log analysis and threat intelligence.

Experience

Work history, roles, and key accomplishments

Current

Security Analyst Home Lab

Current

Home SOC Lab

Mar 2025 - Present (5 months)

Deployed an Azure VM with Microsoft Sentinel, collecting Sysmon, Windows, and DNS logs from three endpoints and tuning analytic rules to reduce false positives by 30%. Simulated brute-force, phishing, and C2 traffic using Atomic Red Team, generating over 50 alerts per week and documenting triage procedures.

Azure Sentinel Sysmon Red Team Incident Response Log Analysis

Security Analyst Training

TryHackMe

Jan 2025 - Present (7 months)

Completed over 20 rooms covering log analysis, SIEM search, and threat intelligence fundamentals, achieving a 95% overall score. Practiced public write-ups demonstrating step-by-step detection and remediation techniques.

Log Analysis SIEM Threat Intelligence Detection Engineering

Education

Degrees, certifications, and relevant coursework

California State Polytechnic University, Pomona

Master of Science, Information Security

2024 -

Actively pursuing an M.S. in Information Security, expected to graduate in August 2026. This program focuses on advanced topics in cybersecurity, preparing for roles in defending organizations against sophisticated threats.

Western Governors University

Bachelor of Science, Information Technology

2020 - 2024

Completed a Bachelor of Science in Information Technology, focusing on foundational IT concepts and practices. This degree provided a comprehensive understanding of various technology domains.