Cybersecurity ISSE

Leidos is dedicated to making the world a safer place by helping our customers in the Defense Industry achieve their critical missions. Our dedicated Defense Group employees are solving critical challenges across the globe. At Leidos, we deliver innovative solutions through the efforts of our diverse and talented people who are dedicated to our customers' success. We empower our teams, contribute to our communities, and operate sustainably.

Everything we do is built on a commitment to do the right thing for our customers, our people, and our community. Our Mission, Vision, and Values guide the way we do business.

Leidos is looking for a cleared Cybersecurity Information System Security Engineer (ISSE) to work in our Beavercreek, OH near Wright Patterson AFB. This role will support our diverse portfolio of programs through software design and development, hardware interfacing and integration, laboratory experimentation, ground and flight testing to deploy cutting‑edge, next‑generation solutions.

• Engineer cybersecurity solutions into mission systems, software applications, networks, lab environments, and integrated hardware/software platforms throughout the system lifecycle.
• Translate cybersecurity requirements, NIST SP 800-53 controls, RMF objectives, customer requirements, and mission needs into implementable technical designs, configurations, and verification methods.
• Develop, review, and maintain cybersecurity architecture artifacts, including security design descriptions, network/security boundary diagrams, data flow diagrams, control implementation details, interface descriptions, and system hardening approaches.
• Support cybersecurity design decisions for tactical networking and communications environments, including boundary protection, segmentation, authentication, encryption considerations, logging visibility, and performance or storage tradeoffs in constrained environments.
• Partner with software, hardware, network, and systems engineering teams to design and implement secure configurations, authentication and authorization mechanisms, logging/auditing, encryption, boundary protections, vulnerability mitigations, and secure system interfaces.
• Support secure system integration in Software Integration Laboratory and test environments, including Linux system hardening, scripting/automation, vulnerability remediation, tool integration, and security configuration management.
• Perform technical security assessments of systems, components, and configurations to identify design gaps, implementation weaknesses, vulnerabilities, and cyber risk; recommend and implement engineering‑based remediation plans.
• Lead or support vulnerability management activities, including interpreting Tenable Nessus, SCAP, STIG, ACAS, or similar scan results; validating findings; developing technical fixes; coordinating remediation with engineers; and verifying closure.
• Design and implement mitigations for vulnerabilities discovered during system scans, security audits, integration events, ground testing, and flight‑test preparation.
• Support implementation and validation of security controls, including documenting how controls are technically satisfied, identifying residual risk, and providing objective evidence for RMF authorization packages.
• Participate in design reviews, engineering review boards, configuration control boards, cyber risk reviews, and test readiness events to ensure cybersecurity considerations are addressed before system deployment.
• Develop or contribute to cybersecurity test procedures, security verification methods, risk assessments, and technical inputs for RMF artifacts, POA&Ms, system security plans, and authorization documentation.
• Assess cybersecurity events, anomalies, and system deficiencies to determine technical impact, root cause, mission risk, and corrective actions.
• Collaborate with ISSMs, ISSOs, system owners, and customer stakeholders to align technical cybersecurity implementation with program compliance, authorization, and operational objectives.
• Support continuous improvement of cybersecurity engineering practices, including automation, secure configuration…