25D Cyber Network Defender Jobs in California (NOW HIRING)

THIS POSITION REQUIRES AN ACTIVE US GOVERNMENT SECURITY CLEARANCE. IF YOU DO NOT HAVE A CLEARANCE, PLEASE DO NOT APPLY.

Cybersecurity Engineer

SG2 Recruiting has partnered with Lumbee Holdings to spearhead the search for a visionary Cybersecurity Engineer. This is a pivotal opportunity to join a dynamic team and directly influence the company’s next phase of growth. If you are a strategic thinker ready to make a tangible impact, we want to hear from you.

Company Overview: At Lumbee Holdings, we deliver mission-critical logistical, technical, and analytical support to empower strategic government and defense operations. Our culture is built on continuous improvement, operational integrity, and dedicated service to key defense stakeholders. When you join our team, you become part of a collaborative environment where your expertise directly supports military readiness and system efficiency.

Your Role: As a Cybersecurity Engineer, you will deliver software assurance testing expertise and cybersecurity engineering support across both offensive assessment findings and independent engineering analysis for the MCTSSA Cyber Branch at Camp Pendleton, CA. You will serve as the team’s primary technical link between offensive findings and implementable engineering changes that make Marine Corps systems more survivable and defensible for Defensive Cyber Operations (DCO) operators. Your core focus includes static and dynamic code analysis, Security Posture Assessments, STIG hardening guidance, vulnerability mitigation engineering, and DCO integration.

What You Will Be Doing

• Develop Mitigation Strategies: Create detailed, technically grounded vulnerability mitigation recommendations tailored to the operational constraints of Marine Corps programs of record.

• Hardening & STIG Implementation: Provide guidance on hardening system and network configurations based on STIGs, SRGs, and industry best practices across Windows, Linux, Cloud, and network environments.

• Enhance DCO Capabilities: Analyze systems and recommend structural changes to improve DCO Marines' ability to monitor, detect, and respond to adversarial activity (e.g., logging standards, sensor placement, alert thresholds).

• Integrate DCO Systems & Playbooks: Assist in connecting program systems to designated DCO providers and produce DCO System Playbooks that outline incident response procedures.

• Execute Scans & Vulnerability Management: Run ACAS vulnerability scans, analyze results, propose remediation actions, and monitor the ongoing application security posture for ISSM reporting.

• Automate Security Tasks: Utilize PowerShell, JavaScript, or Python to automate repetitive cybersecurity engineering, analysis, and reporting tasks.

• Investigate Cyber Incidents: Support breach investigations by analyzing multiple data sources to identify indicators of compromise (IoCs).

• Author Technical Reports: Draft clear client reports explaining technical findings, engineering rationale, and remediation steps for non-technical Program Office stakeholders.

What You Will Need

Must-Haves

• Security Clearance: Active DoD Secret Security Clearance.

• Cybersecurity Experience: At least five (5) years of demonstrated experience in cybersecurity engineering and software assurance.

• Analysis & Forensics Tools: At least two (2) years of hands-on experience utilizing tools such as Wireshark, FTK, Autopsy, or similar technologies.

• Coding & Scripting: At least one (1) year of experience developing code or scripts in languages such as Python, C/C++, Ruby, or PowerShell for automation and analysis.

• IT Infrastructure Support: Hands-on experience in administration, configuration, and support of operating systems, network components, and application security.

• Location/On-Site: Willingness and ability to work 100% on-site at Camp Pendleton, CA.

Nice-to-Haves

• Certifications: DoD IAT Level I or Level II certification (e.g., Security+ CE, CySA+), or software assurance certifications like CSSLP or OSED.

• Education: Bachelor’s Degree in Cybersecurity, Computer Science, or an equivalent technical field.

• Frameworks & Tools: Hands-on experience with DoD and Marine Corps Risk Management Framework (RMF), STIG implementation, and ACAS/Nessus vulnerability management.

Military & Veteran Equivalents: We strongly encourage transitioning service members and veterans to apply! Candidates with backgrounds in the following military occupational specialties (MOS), Air Force Specialty Codes (AFSC), and Navy Ratings/NECs are exceptionally well-suited for this role:

• U.S. Army MOS/WO: 17C (Cyber Operations Specialist), 25D (Cyber Network Defender), 170A/170L (Cyber Warfare Technician Warrant Officer).

• U.S. Air Force AFSC: 1B4X1 (Cyber Warfare Operations), 1D7X1 (Cyber Defense Operations).

• U.S. Navy Rating: CWT (Cyber Warfare Technician) or IT (Information Systems Technician).

Logistics

• Work Location: MCTSSA Cyber Branch – Camp Pendleton, California (Standard business hours: Mon–Fri, 8:00 a.m. – 5:00 p.m.)

• Position Type: On-site, full-time, Exempt

• Travel Required: Less than 10% CONUS travel

• Salary Range: $110,000.00 To $120,000.00 Annually

• Benefits: Comprehensive benefits package (detailed terms and eligibility provided during onboarding)

Mental and Physical Demands: This position is primarily sedentary and performed in an office setting, requiring extended periods of computer use, close visual attention to technical detail, and the ability to sit or stand for extended periods. Occasional lifting of computer or lab equipment up to 25 lbs. may be required.

Related Duties as Assigned: To support evolving mission priorities and organizational goals, the Program Manager or MCTSSA Cyber Branch Lead may assign you additional operational, technical, or cybersecurity tasks.

Equal Employment Opportunity & Disability Accommodations: Lumbee Holdings is an Equal Opportunity Employer. We do not discriminate in employment opportunities or practices on the basis of race, color, religion, sex (including pregnancy, sexual orientation, or gender identity), national origin, age, disability, protected veteran status, genetic information, or any other characteristic protected by applicable federal, state, or local law.

We are committed to providing reasonable accommodations to qualified individuals with disabilities in all phases of the employment process, including the application and interview phase. If you require a reasonable accommodation to participate in the application or recruitment process, please inform your recruiter or contact our HR team.