Senior Information Systems Security Engineer (ISSE)

Amentum•Fort Meade, MD

4d•$190,000 - $225,000•Onsite

About The Position

Amentum is seeking a Senior Information Systems Security Engineer (ISSE) to support DISA and the Department of Defense at Fort Meade, Maryland. The role supports mission-critical IT capabilities by helping engineer, integrate, deploy, and sustain secure enterprise systems for national security and intelligence missions. The Senior ISSE leads the design, integration, and assessment of security architectures for systems processing classified and sensitive intelligence information. The position applies systems security engineering throughout the system lifecycle, ensures compliance with Intelligence Community and national security policy, and advises program leadership and Authorizing Officials on risk. It requires significant technical independence, mentoring, and influence over enterprise security decisions. The work schedule is eight hours per day, Monday through Friday. The employee works daily in a SCIF and may also work in a datacenter for specified periods. The role requires an active Top Secret clearance with SCI eligibility. A bachelor's degree in cybersecurity, computer science, engineering, or a related field and 8–12 years of relevant experience are specified, though additional experience may substitute for education. At least five years of ISSE or equivalent security engineering experience in classified or IC environments is required. One or more of CISSP, CISM, or CASP+ is required. Compensation is listed as $190,000–$225,000.

Requirements

Active Top Secret clearance with SCI eligibility.
Bachelor's degree in cybersecurity, computer science, engineering, or a related field, plus 8–12 years of relevant experience; additional experience may substitute for education, including typically four additional years in lieu of a degree.
At least five years performing ISSE or equivalent security engineering duties in classified or IC environments.
Demonstrated experience executing the RMF and producing authorization artifacts for national security systems.
Working knowledge of network security, Windows/Linux operating system hardening, identity and access management, encryption/PKI, and auditing/logging.
Experience supporting classified networks, cross-domain solutions, or multi-enclave environments.
Experience with cross-domain solutions, classified cloud environments, or zero trust implementation.
Familiarity with automation and scripting such as Python, PowerShell, or Ansible, and infrastructure-as-code security.
Experience with SIEM, vulnerability management, and continuous monitoring tools such as ACAS/Nessus, Splunk, and eMASS or an agency equivalent.
Expert knowledge of information systems security principles, defense-in-depth, and threat modeling.
Familiarity with ACAS, STIG Viewer, SCAP, and Assured Compliance tools.
Experience supporting ATO packages for cloud environments, including C2S or commercial cloud for classified workloads.
Familiarity with IC-specific tools and processes for reciprocity and enterprise authorization.
Experience briefing Authorizing Officials, program managers, and senior leadership.
Strong understanding of security control families and control implementation, inheritance, and assessment procedures.
Ability to translate technical findings into clear risk statements and policy into practical guidance for system administrators.
Excellent written communication, attention to detail, and ability to produce thorough documentation.
Ability to manage multiple systems, authorization packages, and competing deadlines.
Sound judgment when handling classified and sensitive information.
Ability to work independently and within cross-functional teams.
Hands-on experience managing system records, controls, artifacts, and POA&Ms in eMASS.
Working knowledge of the RMF, NIST SP 800-37, 800-53, and 800-53A, CNSSI 1253, and ICD 503.
Thorough knowledge of IC and national security information-system policy, including CNSS issuances and agency directives.
Skill in assessing risk and applying technical, operational, and management controls.
One or more of the following certifications: CISSP, CISM, or CASP+.

Nice To Haves

CISSP Information System Security Engineering Professional (ISSEP).
Certified Information System Auditor (CISA).

Responsibilities

Develop and review security architectures, designs, and requirements for classified enclaves, cross-domain solutions, cloud environments, and mission applications.
Integrate security controls into system development lifecycles, including DevSecOps pipelines.
Evaluate emerging technologies, including zero trust, cloud services, AI/ML tools, and containerization, and recommend risk-informed adoption strategies.
Define and validate security requirements traceable to mission needs, threat models, and applicable controls.
Lead system categorization, control selection and tailoring, implementation, assessment, and continuous monitoring under the IC Risk Management Framework.
Prepare and maintain authorization packages, including System Security Plans, Security Assessment Reports, POA&Ms, and risk assessments.
Brief ISSMs, Authorizing Officials, and program leadership on residual risk and recommended mitigations.
Support reciprocity and inheritance of controls across IC elements and accrediting bodies.
Analyze vulnerability scan results, configuration baselines, and penetration test findings, and drive remediation with system owners and engineering teams.
Support incident response through technical analysis, root-cause determination, and incorporation of lessons learned into system designs.
Review change requests and configuration changes for security impact.
Support audits, inspections, and security reviews by oversight bodies.
Interpret and apply IC and national security policies, including ICD 503, ICD 705 and its technical specifications, CNSSI 1253, NIST SP 800-37/53/53A, and agency directives.
Participate in configuration control boards, architecture review boards, and security working groups.
Coordinate with counterintelligence, physical security, supply chain risk management, and cross-domain teams.
Mentor junior and mid-level ISSEs and security analysts.
Serve as a technical authority and escalation point for complex or ambiguous security issues.
Translate technical risk into clear, actionable guidance for non-technical decision makers.
Produce high-quality technical documentation and contribute to standards, templates, and best practices.
Balance mission needs against security requirements using sound judgment.
Comply with applicable safety, quality, operational, and environmental plans, procedures, and policies.