Senior Information System Security Engineer

As a Information System Security Engineer (ISSE) you will play a critical role in ensuring the confidentiality, integrity, and availability of information systems across their life-cycle. The ISSE conducts comprehensive information system security engineering activities that define, refine, and implement security requirements through deliberate system design, development, and configuration. This position directly supports the secure engineering of systems operating within Special Access Programs (SAPs) and other highly controlled Department of Defense (DoD) environments.

Primary Responsibilities

• Lead and execute information system security engineering processes to capture, analyze, and refine security requirements in alignment with organizational and DoD policy.
• Architect, design, and implement security solutions that are integrated into new and existing information systems throughout their development lifecycle.
• Collaborate with system architects, developers, and administrators to ensure security requirements are embedded early in design and configuration decisions.
• Apply best practices in software and systems engineering methodologies, including secure architecture, secure coding techniques, and defense-in-depth strategies.
• Evaluate and advise on system upgrades, modernization efforts, and technology integrations, ensuring continued compliance with DoD and SAP security standards.
• Support risk management and accreditation activities by contributing to documentation, system assessments, and security test and evaluation (ST&E) efforts.
• Provide technical security guidance to system owners, developers, and administrators on implementation of security controls per JSIG, NIST SP 800-53, DoDI 8500.01, and related directives.
• Coordinate with Information System Owners (ISO), Authorizing Officials (AO), and ISSM/ISSO to verify that systems meet security design and implementation requirements.
• Responsible for ensuring the information system is engineered and deployed with appropriate safeguards.

• 20+ years of Information Assurance related work within the Department of Defense (DoD) or Intelligence Community (IC), work experience must be no less than two total years of experience in a SAP and/or SCI environment (at least one year of work in the last five years)
• Experience in information system security engineering, cybersecurity architecture, or secure software/system development.
• Knowledge of DoD RMF, NIST SP 800-37/53, and CNSSI 1253 processes.
• Familiarity with cross-domain solutions, encryption technologies, identity and access management, and secure configuration baselines.
• Advanced technical competency in one or more of the following supported platforms: Microsoft Windows Server, Active Directory, Red Hat Enterprise Linux servers, MS Hyper- V/VMWare/ESx/Xen Hypervisors, Enterprise networking/firewalls/intrusion detection/prevention systems, forensic analysis/vulnerability assessment, Group Policy management and configuration.

Education Requirements:

• Bachelor’s degree in Computer Science, Cybersecurity, Information Systems, or related field.

Clearance Requirements:

• Current/active Top Secret/SCI; Current or recent DoD SAP access
• Subject to a Counterintelligence (CI) polygraph

The pay range for this position is $180,000/year to $230,000/year; however, base pay offered may vary depending on established government contract ranges, job-related knowledge, skills, and experience, and other factors. MTSI offers a full range of medical benefits, 401k, ESOP, paid time off, and other benefits, dependent on the position offered. Base pay information is based on market location. Applications will be accepted on an ongoing basis. This posting will be renewed periodically until the position is filled.