Information System Security Engineer at Modern Government Solutions; MGS Tysons Corner, VA

Overview

Information System Security Engineer job at Modern Government Solutions (MGS). Tysons Corner, VA.

TITLE: Information Systems Security Engineer (ISSE)

LOCATION: Tysons, VA

CLEARANCE REQUIRED: Active DoD TS/SCI Clearance

EMPLOYMENT TYPE: Full-time, On-site

TRAVEL: Up to 30%

Modern Government Solutions (MGS) is seeking an Expert ISSE to provide expertise on security requirements for the design, implementation, and deployment of high-performance compute, storage, and network infrastructures. The role serves as the primary advisor to the program Chief Engineer and a liaison to Accrediting Officials, focusing on security-related design and accreditation policies.

RESPONSIBILITIES (not limited to):

• Develop, implement, and review security requirements, plans, and documentation to ensure system compliance with RMF, ICD 503, and NISPOM standards, including system security plans, traceability matrices, and disaster recovery.
• Perform security assessments, risk analysis, and continuous monitoring across networks, systems, and cloud environments, coordinating with stakeholders to optimize compliance and mitigate vulnerabilities.
• Lead vendor-side efforts in system accreditation and Authority to Operate (ATO)/Authority to Connect (ATC) processes, ensuring secure deployment and compliance.
• Support the A&A lifecycle, including system hardening, software assessments, test planning, and Information Security Assessment Program reviews.
• Collaborate with development teams, engineers, and security offices to ensure adherence to security standards across diverse network platforms.

• Must possess an active Department of Defense (DoD) TS/SCI with Counterintelligence Polygraph security clearance.
• Bachelor's Degree in Computer Science, Networking, Systems Engineering or security-related fields. Work experience in relevant fields may be considered for equivalency.
• 10+ years of experience in system security certification and accreditation.
• Recent and relevant experience in accrediting systems in NRO programs.
• Proven experience leading RMF and ATO processes on behalf of a vendor or contractor, including full lifecycle system accreditation and stakeholder coordination.
• Familiarity with, and access to, Iron Mountain Data Center facilities.
• Strong interpersonal, organizational, and time management skills, with the ability to work both independently and collaboratively in team settings.
• Proven expertise in developing, documenting, and communicating complex plans, identifying and mitigating risks, and ensuring effective execution.

• CISSP (DOD 8570).
• Excellent communication and interpersonal skills.
• Familiarity with security accreditation-related documentation.
• Troubleshooting, root cause assessment and POA&M development.
• ITIL Foundations.
• Familiarity with tools including Nessus and Splunk.

Applicants selected will be United States citizens subject to a government security investigation and must meet eligibility requirements for access to classified information. *

At MGS, we believe a people-first culture corresponds to organizational success through a commitment to excellence, integrity, inclusion, and an attitude that welcomes challenges meets demands, sustains growth, and drives innovation. We provide expert mission-first technical and programmatic services and solutions for the US intelligence community, the US Department of Defense, and other governmental agencies. We create people-first organizational cultures where employees feel needed in the system, not a system that needs employees.

We provide you with long-term career opportunities centrally focused on our core value system: inclusion, integrity, and a commitment to excellence.

MGS is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status, and will not be discriminated against on the basis of disability.