Information Systems Security Engineer

System One; Clarksburg (MD); On-site; USD 162,000 - 198,000; Full time

Job summary

System One in Clarksburg, MD seeks an Information Systems Security Engineer (ISSE) to support mission-critical, classified systems. You will apply cybersecurity engineering best practices across design, implementation, authorization, and ongoing compliance.

Hands-on with RMF, A&A, ATO sustainment, and vulnerability/stig compliance efforts, you will collaborate with security and technical teams to build secure, auditable systems and continuous monitoring processes.

Qualifications

• Active TS/SCI clearance is required.
• DoD 8570/8140 IASAE Level II compliant certification is required.
• Strong RMF knowledge and A&A/ATO experience.
• Experience implementing security controls and continuous monitoring.
• Familiarity with NIST SP 800-37 and SP 800-53.
• Experience with RMF/cybersecurity tools.

Responsibilities

• Support full RMF lifecycle for classified systems from planning through continuous monitoring.
• Contribute to A&A packages and maintain ATOs over time.
• Implement, assess, and validate security controls and requirements.
• Build and maintain RMF documentation and evidence artifacts.
• Define system boundaries and document security architecture.
• Run and analyze compliance scans and validate results.
• Support STIG implementation, hardening, remediation verification, and patch validation.
• Participate in Continuous Monitoring activities and reporting.

Skills

Active TS/SCI clearance

RMF knowledge

A&A experience

Documentation skills

NIST SP 800-37/53 familiarity

Security compliance tools familiarity

Tools

LATTEART

XACTA

BISCOTTI

WATCHCAT

STE

Job description

INFORMATION SYSTEMS SECURITY ENGINEER (ISSE)

LOCATION AND GENERAL DETAILS

Location: Clarksburg, Maryland
Work Model: Onsite
Type: Direct Hire
Compensation: $180,000 (salary)
Schedule: 40 hours/week
Clearance Required: Active TS/SCI with Polygraph (must be current)
Certification Required: DoD 8570/8140 IASAE Level II (compliant)

ROLE OVERVIEW

We’re hiring an Information Systems Security Engineer (ISSE) to support mission‑critical work in a classified environment. In this role, you’ll help build, secure, and maintain systems by applying cybersecurity engineering best practices across design, implementation, authorization, and ongoing compliance.

You’ll be hands‑on with the Risk Management Framework (RMF), Assessment & Authorization (A&A), ATO sustainment, control validation, continuous monitoring, and vulnerability/stig compliance efforts—partnering closely with security and technical teams.

WHAT YOU’LL DO

• Support the full RMF lifecycle for classified systems (from planning through continuous monitoring)
• Contribute to A&A packages and help maintain ATOs over time
• Implement, assess, and validate security controls and technical requirements
• Build and maintain RMF documentation and “body of evidence” artifacts
• Support system boundary definition and security architecture documentation
• Run and analyze compliance/vulnerability scans; validate results (including false positives)
• Support STIG implementation, configuration hardening, and remediation verification
• Help manage patch validation and ongoing security compliance activities
• Participate in Continuous Monitoring (ConMon) activities and reporting

REQUIRED QUALIFICATIONS (MUST HAVE)

• Active TS/SCI with Polygraph security clearance
• DoD 8570/8140 IASAE Level II compliant certification (required)
• Strong working knowledge of RMF
• Experience supporting A&A activities and ATO processes
• Experience implementing/validating security controls and supporting continuous monitoring
• Familiarity with NIST SP 800-37 and NIST SP 800-53 (Rev. 3 and/or Rev. 5)
• Experience with RMF/cybersecurity tools such as: LATTEART, XACTA, BISCOTTI, WATCHCAT, STE
• Experience using compliance and configuration scanning tools
• Strong documentation, analytical, and troubleshooting skills

NICE TO HAVE

• Experience working in classified cybersecurity environments
• Familiarity with enterprise Linux, networking, and/or cloud environments
• Experience partnering with ISSOs, ISSMs, SCAs, and System Owners
• Experience supporting large‑scale enterprise or mission systems
• Exposure to vulnerability management automation and reporting workflows

CERTIFICATION EXAMPLES (IASAE LEVEL II)

Common qualifying certifications include:

• CISSP
• CASP+
• CCSP
• CSSLP

System One, and its subsidiaries including Joulé and Mountain Ltd., are leaders in delivering outsourced services and workforce solutions across North America. We help clients get work done more efficiently and economically, without compromising quality. System One not only serves as a valued partner for our clients, but we offer eligible employees health and welfare benefits coverage options including medical, dental, vision, spending accounts, life insurance, voluntary plans, as well as participation in a 401(k) plan.

System One is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, age, national origin, disability, family care or medical leave status, genetic information, veteran status, marital status, or any other characteristic protected by applicable federal, state, or local law.

#M-1
#LI-
Ref: #851-Rockville-S1