Senior Information Systems Security Engineer Security Clearance

Overview

Senior Information Systems Security Engineer TS/SCI with polygraph Reston, VA

• Provide end-to-end security engineering across hybrid, cloud, and air-gapped environments.
• Design, engineer, assess, and sustain security controls across complex system architectures, ensuring compliance, operational readiness, and mission resilience.
• Engineer, implement, and manage security solutions (firewalls, IDS/IPS, endpoint protection, encryption).
• Perform security assessments across systems, applications, and networks.
• Implement, validate, and maintain RMF NIST 800-53 controls across on-prem, cloud, and air-gapped systems.
• Conduct STIG checks, hardening, and secure configuration updates for OS, applications, network devices, and cloud resources.
• Run ACAS/Tenable scans, analyze vulnerabilities, and drive remediation with engineering teams.
• Configure log ingestion, parsing, and data flows into SIEM platforms (Splunk), and build dashboards and alerts.
• Monitor network traffic, logs, and events to detect anomalies and security threats.
• Conduct incident investigations and provide technical recommendations for mitigation.
• Maintain and enhance incident response plans and continuous monitoring procedures.
• Engineer, configure, and modify secure system and network baselines; analyze and troubleshoot network protocols, packet flows, and configuration issues.
• Produce RMF artifacts, POA&Ms, scan reports, dashboards, and security documentation.
• Collaborate with Dev Sec Ops , system engineering, IT, and development teams to embed security into the lifecycle.
• Write user stories, define security acceptance criteria, and support regression testing.
• Perform system assessments and security engineering within air-gapped and restricted networks.
• Support ongoing continuous monitoring activities and security control reviews.

• 7+ years cybersecurity/ISSE experience designing, implementing, and assessing security controls.
• Strong experience with RMF, NIST 800-53, STIGs, ICD 503, FISMA, FedRAMP.
• SIEM experience, including log configuration, dashboards, and analytics (Splunk preferred).
• Hands-on ACAS/Tenable vulnerability scanning and analysis.
• Cloud security experience (AWS/Azure/Gov Cloud) in IL5-IL6 environments.
• Strong understanding of network protocols, OS internals, and infrastructure security.
• Skilled in incident response and forensic analysis.
• Experience with Fortify, Acunetix, Prisma Cloud.
• Experience configuring/modifying secure system and network baselines.
• Familiarity with agile workflows, user stories, and regression testing.
• Experience working in air-gapped or disconnected environments.
• Strong communication skills for both technical and non-technical audiences.
• CISSP or DoD 8140-approved certification.
• Active TS/SCI with CI poly.

• Medical, Dental and Vision Plans
• Generous PTO Policy
• 401(k)
• HSA and FSA options
• Life and Disability Insurance
• Tuition Reimbursement and Training
• Perks at Work Discount Program
• Referral Program
• Leads Generation Program
• College America 529
• Fitness Reimbursement Program
• Travel Assistance
• Norton Lifelock Benefit Solutions
• Life Planning Financial & Legal Services