Senior ISSO - Cloud & RMF Security Lead (TS/SCI)

Guidehouse; Springfield (VA); On-site; USD 150,000 - 190,000; Full time

Benefits offered by this job

Medical Insurance

Dental & Vision Insurance

401(k) Retirement Plan

Life Insurance

Student Loan PayDown

Tuition Reimbursement

Job summary

Guidehouse seeks an experienced Information Security Systems Officer (ISSO) to lead RMF/ATO activities for a major federal program. You will guide system owners, engineers, and security teams through cloud security architecture across AWS, Azure and hybrid environments.

The role requires a Top Secret/SCI poly, strong knowledge of NIST RMF, and hands-on experience with SIEM, vulnerability scanners, and endpoint protection. Expect collaboration with DevSecOps and cross-functional teams.

Qualifications

• Bachelor’s degree from an accredited university.
• Minimum of five (5) years of work experience in cybersecurity or secure systems engineering with cloud architecture.
• Active and maintained TS/SCI Poly Federal or DoD security clearance with CI polygraph or FS/FSP.
• US Citizenship is required.
• Strong understanding of security frameworks and compliance standards (NIST RMF SP 800-53 Rev 5, DoD 8570).
• Experience designing and implementing enterprise security tools (SIEM, vulnerability scanners, endpoint protection).
• Ability to lead cross-functional teams and manage complex projects.
• Excellent communication skills to convey technical concepts to non-technical stakeholders.

Responsibilities

• Lead design and engineering of secure cloud architectures across AWS, Azure, and hybrid environments.
• Implement and validate NIST 800-53 controls and cloud-native security services (IAM, encryption, logging).
• Conduct cloud threat modeling, risk assessments, and architecture reviews.
• Oversee cloud baselines using STIGs, CIS Benchmarks, and SCAP.
• Drive cloud vulnerability and compliance efforts with ACAS/Nessus and cloud posture tools.
• Support RMF engineering activities including boundary definitions and authorization packages.
• Integrate cloud-security capabilities like Sentinel, Splunk, and SIEM pipelines.
• Guide DevSecOps teams on secure CI/CD, container security, and IaC validation.
• Produce cloud diagrams, design docs, and engineering artifacts.
• Mentor ISSEs and serve as escalation point for cloud engineering issues.

Skills

Cloud security

RMF/ATO guidance

NIST 800-53

Active TS/SCI Poly

Cloud architecture

SIEM (Splunk)

Vulnerability management (Nessus)

CrowdStrike

Leadership

Communication

US Citizenship

Education

Bachelor’s degree

Master’s degree

Tools

Splunk

Nessus

CrowdStrike

Job description

Guidehouse seeks an experienced Information Security Systems Officer (ISSO) to lead RMF/ATO activities for a major federal program. You will guide system owners, engineers, and security teams through cloud security architecture across AWS, Azure and hybrid environments.

The role requires a Top Secret/SCI poly, strong knowledge of NIST RMF, and hands-on experience with SIEM, vulnerability scanners, and endpoint protection. Expect collaboration with DevSecOps and cross-functional teams.