Cyber Systems Engineer / Information System Security Engineer (ISSE)

About the role

Amentum is hiring a Cyber Systems Engineer / Information System Security Engineer (ISSE) to safeguard national security by protecting the integrity, confidentiality and availability of government-affiliated information systems. The engineer acts as the primary security advisor for assigned systems, working with engineers, system administrators, government clients and security assessors to identify, mitigate and monitor cybersecurity risks in line with DoD and DIA standards.

Key responsibilities

• Lead Assessment and Authorization (A&A) efforts under the Risk Management Framework (RMF) and Intelligence Community Directives (ICD), coordinating with Group-level ISSMs and Security Controls Assessors
• Develop and maintain security documentation such as SSPs, CONOPS, contingency plans, user guides and SOPs
• Collect and analyze security artifacts (Bodies of Evidence) and support POA&Ms mitigation
• Track progress toward ATD, IATT and ATO milestones and keep project A&A status current
• Support audits and compliance assessments, including ISCM and OA Strategy Plan updates
• Evaluate emerging threats, advise on High Value Assets and TS/SCI or Secret systems, and update control volatility sections of security plans
• Review A&A documentation for technical accuracy, compliance and readability

Required profile

• Bachelor's degree in Cybersecurity, Information Technology, Computer Science or a related field (relevant experience may substitute)
• 3-5 years of experience in information system security or cybersecurity roles
• DoD 8570.01-M IASAE Level II certification, held and maintained
• TS/SCI clearance with polygraph
• Experience with A&A processes, audits, threat modeling and security posture assessments

Required skills

• Deep understanding of the RMF lifecycle and ICD 503
• Ability to interpret security requirements and guide implementation across complex architectures
• Familiarity with DIA policies, DoD directives and federal cybersecurity laws
• Knowledge of HVA protection and TS/SCI and Secret classification protocols
• Writing and technical editing skills, and familiarity with tools such as SharePoint, Confluence and Git