Information Systems Security Engineer - TS/SCI

Parsons Corporation is seeking an Information Systems Security Engineer to support a Department of Defense system. The role is responsible for vulnerability management, system patching, POA&M remediation, security alert response, documentation, configuration management, and compliance with the NIST Risk Management Framework and NIST SP 800-53 controls.

Responsibilities:

• Vulnerability Management: Conduct monthly System Security Plan (SSP) ACAS Vulnerability Scans and quarterly ACAS Security Technical Implementation Guide (STIG) / SCAP Scans
• System Maintenance & Patching: Perform monthly SSP patch version upgrades to ensure systems remain secure and compliant
• Compliance & Auditing: Conduct annual manual STIG checks on system components that cannot be scanned automatically
• POA&M Remediation: Act as the primary technical remediator for POA&M findings, executing remediation tasks tracked via Jira tickets generated by the ISSO
• Incident & Alert Response: Assist the ISSO with investigating and responding to security alerts and logs
• Documentation & Configuration Management: Maintain and update critical security documentation, including network/system diagrams, Hardware/Software (HW/SW) lists, and Ports, Protocols, and Services Management (PPSM) documentation
• RMF Support: Assist the ISSO in drafting, updating, and maintaining NIST RMF documentation in accordance with NIST SP 800-53 guidelines

Requirements:

• Active TS/SCI
• Bachelor's degree in Cybersecurity, Computer Science, Information Technology, Engineering, or a related technical field (or equivalent years of relevant work experience)
• Minimum of 4+ years of hands-on experience in cybersecurity engineering, systems administration, or a related technical role within a DoD or federal environment
• Must hold an active baseline certification for Information Assurance Technical (IAT) Level II or Level III (e.g., CompTIA Security+ CE, CASP+ CE, CISSP, or equivalent)
• Proven hands-on experience using Assured Compliance Assessment Solution (ACAS) / Tenable Nessus for vulnerability and compliance scanning
• Strong technical background in applying and validating DISA STIGs across various operating systems (e.g., Windows, Linux) and network devices
• In-depth knowledge of the NIST Risk Management Framework (RMF) and NIST SP 800-53 security controls
• Experience with patch management and system upgrades in a secure, air-gapped, or highly regulated environment
• Familiarity with tracking workflows and remediating technical tasks using Jira or similar ticketing systems
• Ability to translate technical vulnerabilities into actionable remediation steps
• Excellent communication skills and the ability to work collaboratively with the ISSO and other stakeholders
• Advanced scripting skills (e.g., PowerShell, Python, Bash) to automate STIG application and compliance checks
• An active Top Secret SCI security clearance is required for this position
• Advanced degree is preferred
• Experience configuring and analyzing logs within OpenSearch, Elasticsearch, or similar SIEM/log analysis tools
• Familiarity with DoD PPSM (Ports, Protocols, and Services Management) processes and registry requirements
• Operating System/Computing Environment (CE) certifications (e.g., Microsoft Certified: Azure Administrator, Red Hat Certified System Administrator)
• Experience with developing network and rack diagrams in Visio