What are the responsibilities and job description for the Cybersecurity Systems Administrator (TS/SCI w/ CI POLY) position at Marathon TS?
A large Engineering customer of Marathon TS is seeking an experienced Systems Administrator to join their dynamic team.
Marathon TS is seeking a highly skilled Cybersecurity System Administrator to support a secure operational technology environment by integrating advanced system administration with proactive cybersecurity operations. This dual-role position requires an individual with both hands-on technical expertise in managing modern enterprise IT systems and a deep understanding of federal cybersecurity frameworks and risk management.
Primary Responsibilities: System Administration Duties
- Install, configure, upgrade, and maintain enterprise systems including:
- Windows Server 2019/2022, Windows 10, RHEL 7/8
- VMware ESXi / vSAN infrastructure
- Web browsers, Adobe Acrobat, and other desktop applications
- Manage virtual machines and storage in a VMware vSAN environment.
- Administer Microsoft SCCM, WSUS, Active Directory (AD), Group Policy (GPO), and perform system patching and image deployment.
- Integrate and maintain vendor systems and third-party applications within a Windows ecosystem.
- Operate and manage jump (bastion) hosts for network segregation and secure remote access.
- Coordinate with development and support teams to test system hardware/software and optimize performance.
- Provide Tier 1–3 support, troubleshoot incidents, and maintain operational resilience via regular backups and recovery plans.
- Load PKI certificates and maintain change management documentation and incident logs.
Cybersecurity Operations
- Serve as the Information System Security Manager (ISSM) for all assigned systems.
- Monitor networks for real-time threat indicators; investigate and respond to security events.
- Implement and operate cybersecurity tools such as ACAS, NESSUS, SCAP, and STIG Checklists.
- Conduct and remediate vulnerability scans; follow DISA STIGs and IAVA compliance.
- Manage POA&Ms, deviation lists, and ensure systems maintain Authority to Operate (ATO).
- Provide FRCS cybersecurity engineering support and continuous monitoring in accordance with DoD and Army standards.
- Perform penetration testing, threat analysis, and security risk assessments in lab/test environments.
Salary : $130,000 - $150,000