Senior Information Systems Security Engineer (ISSE)

Reston, VA

The Senior Information Systems Security Engineer (ISSE) provides expert cybersecurity engineering support for Authorization and Authorization (A&A), network domain certification, Cross Domain Solutions (CDS), and ongoing risk management. This includes analyzing, designing, implementing, assessing, and continuously monitoring security posture for customer mission systems across unclassified (CAC/PIV) and TS/SCI networks. The role supports integration of cybersecurity into system engineering lifecycles, compliance with DoD/IC policies, and transition toward dynamic, automated risk management practices to maintain operational resilience in a high-tempo environment.

• Lead and support cybersecurity A&A activities, including RMF/CSRMC execution, for multiple systems on unclassified and TS/SCI domains, ensuring compliance with DoD, Army, and IC requirements (e.g., ICD 503).
• Develop, review, and maintain security documentation and artifacts, including System Security Plans (SSPs), security control implementation, risk assessments, and accreditation packages.
• Conduct security control assessments, Security Test and Evaluation (STE), Cybersecurity Test and Evaluation (CTE), technical vulnerability scanning, configuration assessments, and penetration testing; analyze results and manage POA&Ms with effective risk mitigations.
• Perform security engineering for new/existing systems: design and integrate hardware, OS, software, and network solutions that meet categorized security requirements and controls (including support for DevSecOps pipelines where applicable).
• Support continuous monitoring, security metrics reporting, integration testing of safeguards, and ongoing compliance audits/inspections.
• Analyze information sensitivity, data flows, and threats to recommend and implement risk-based security designs, including zero-trust principles where relevant.
• Assist in developing and updating security policies, procedures, and risk management strategies.
• Collaborate with government stakeholders to ensure baselines meet domain standards and authorization-to-connect requirements; provide technical guidance and briefings as needed.
• Support Cross Domain Solution (CDS) assessments and other specialized cybersecurity engineering tasks.
• Provide onsite support in the Reston, VA SCIF at least 4 days per week; occasional after-hours or on-call support may be required.
• Other duties as assigned

• Bachelor’s degree in computer science, Information Assurance, Cybersecurity, Engineering, or related field (or equivalent experience).
• 10+ years of progressive IT/cybersecurity experience, with at least 6+ years directly supporting IC or DoD cybersecurity certification/accreditation, security engineering, or RMF/CSRMC activities.
• DoD 8140 IASAE Level II (or equivalent) certification: CISSP, CASP+, or CSSLP (current and maintained).
• Active TS/SCI clearance required; CI Poly highly preferred.
• Valid state driver’s license
• Successfully pass background and drug screening

Preferred Qualifications:

• Advanced degree or additional certifications (e.g., CCSP, CISM, GIAC, or cloud security credentials).
• Experience with DevSecOps, automation tools, cloud environments, threat modeling, or modern security architectures.
• Prior experience supporting Cross Domain Solutions or enterprise-level continuous monitoring platforms.
• Strong familiarity with tools such as ACAS/Tenable, SCAP, Nessus, or similar

Knowledge, Skills, and Abilities:

• Demonstrated hands-on experience with DoD/Army/IC cybersecurity policies, Risk Management Framework (RMF), evolving Cybersecurity Risk Management Construct (CSRMC), ICD 503, STE/CTE events, and A&A processes.
• Deep expertise in security engineering principles, NIST/CNSSI controls, and practical implementation of safeguards across networks, systems, and applications.
• Ability to rapidly learn and apply new technologies to mission needs in a dynamic environment.
• Strong analytical, problem-solving, and abstract thinking skills; proven ability to visualize and mitigate complex risks.
• Excellent written and verbal communication skills, including preparing high-quality documentation and briefing senior stakeholders.
• Proficient in Microsoft Office suite; experience with collaboration tools a plus.
• Ability to work independently and collaboratively in a team setting, managing multiple priorities under time constraints.
• Customer-service orientation, professional demeanor, and strong interpersonal skills.

How you’ll grow  

At Chenega MIOS, our professional development plan focuses on helping our team members at every level of their careers to identify and use their strengths to do their best work every day. From entry-level employees to senior leaders, we believe there’s always room to learn.  

We offer opportunities to help sharpen skills in addition to hands-on experience in the global, fast-changing business world. From on-the-job learning experiences to formal development programs, our professionals have a variety of opportunities to continue to grow throughout their careers.  

Benefits  

At Chenega MIOS, we know that great people make a great organization. We value our team members and offer them a broad range of benefits.  

Learn more about what working at Chenega MIOS can mean for you.  

Chenega MIOS’s culture  

Our positive and supportive culture encourages our team members to do their best work every day. We celebrate individuals by recognizing their uniqueness and offering them the flexibility to make daily choices that can help them be healthy, centered, confident, and aware. We offer well-being programs and continuously look for new ways to maintain a culture where we excel and lead healthy, happy lives.  

Corporate citizenship  

Chenega MIOS is led by a purpose to make an impact that matters. This purpose defines who we are and extends to relationships with our clients, our team members, and our communities. We believe that business has the power to inspire and transform. We focus on education, giving, skill-based volunteerism, and leadership to help drive positive social impact in our communities.  

Learn more about Chenega’s impact on the world.  

Chenega MIOS News- https://chenegamios.com/news/  

Tips from your Talent Acquisition Team  

We want job seekers exploring opportunities at Chenega MIOS to feel prepared and confident. To help you with your research, we suggest you review the following links:  

Chenega MIOS web site - www.chenegamios.com  

Glassdoor - https://www.glassdoor.com/Overview/Working-at-Chenega-MIOS-EI_IE369514.11,23.htm  

LinkedIn - https://www.linkedin.com/company/1472684/  

Facebook - https://www.facebook.com/chenegamios/ 

#Cyberstar, LLC