Security System Administrator

Job Summary We are seeking an experienced Security System Administrator to support and maintain systems within the enterprise cybersecurity and compliance-driven environment. This role requires a technically proficient professional capable of operating within classified environments, ensuring system integrity, security, and compliance with federal DoD (DoW) standards. Essential Functions Reasonable accommodation may be made to enable individuals with disabilities to perform the essential functions. Administer, maintain, and secure classified information systems in accordance with DoD and organizational policies Perform routine system maintenance, including patching, updates, and vulnerability remediation (e.g., STIG compliance, SCAP scans) Design, deploy, and manage Windows/Linux domains, including Active Directory configuration, Group Policy management, and system hardening Support system accreditation efforts under RMF, including implementation of NIST 800-53 security controls Monitor system performance, logs, and security events; respond to incidents as required Implement and maintain secure configurations for servers, workstations, and network devices Collaborate with ISSM/ISSO, network teams, and engineering staff to ensure continuous compliance and operational readiness Maintain documentation including system configurations, SOPs, and change management records Support audits, inspections, and security assessments (e.g., DCSA reviews) Participate in system buildouts, upgrades, and infrastructure improvements Assist with COMSEC as an ALT COMSEC Manager Position Qualifications In compliance with federal law, all persons hired will be required to verify identity and eligibility to work in the United States and to complete the required employment eligibility verification form upon hire. Competency Statements Adaptability - Adapts to change, open to new ideas and responsibilities Communication - Ability to communicate thoughts clearly, both oral and written in an honest, open and timely manner Job Knowledge - Understands facets of job, aware of duties and responsibilities, keeps job knowledge current Technical Skill - Possesses the knowledge and skills needed to perform a job or role effectively Dependability - Meets deadlines, works independently or in a team environment, is accountable, maintains focus, good attendance record Quality - Strives to eliminate errors, accurate work is a priority, seeks opportunities to improve products Ethics - Honest, accountable, maintains confidentiality Initiative / Take Ownership - Takes action, seeks new opportunities, strives to see projects to completion, meaning own your job and see it through Decision Making – Problem solve and critical thinking skills, be able to reach a decision, takes thoughtful approach when considering options, seeks input from others, makes difficult decisions Customer Focus - Understands and can meet the needs in a customer‑centric (Internal and External) environment and build strong relationships. Promotes a positive image of the company and strives to solve issues raised by customers Experience and Skills 3+ years of experience as a System Administrator in a cybersecurity-focused or compliance-driven environment Hands‑on experience supporting classified systems (CUI, Secret, or higher) Strong knowledge of: Windows Server and/or Linux administration Active Directory, DNS, DHCP, and Group Policy System hardening (STIGs), patch management, and vulnerability remediation Experience with RMF, NIST 800-53 controls, and ATO processes Ability to operate as a Subject Matter Expert (SME) across multiple technical domains Proven ability to work both independently and within cross‑functional teams Strong troubleshooting, analytical, and problem‑solving skills Conduct site visits and attend meetings at various company locations. Travel up to 10% of the time as required. Experience with Special Access Programs (SAP) and SIPRNet Education Required Bachelor’s degree in Computer Science, Information Technology, Cybersecurity, or a related technical field; advanced degree preferred Equivalent combination of education and relevant hands‑on experience (e.g., 3+ years of system administration in secure/classified environments) Preferred Relevant industry certifications such as: Security+ (DoD 8570/8140 compliant) CompTIA CASP+, CompTIA A+, CompTIA Network+ Microsoft, Linux, or VMware certifications (e.g., MCSA/MCSE, RHCSA/RHCE, VCP) Antenna Research Associates, Inc. is an equal opportunity employer committed to a policy of non-discrimination and affirmative action. We do not discriminate based on race, color, religion, sex, national origin, disability, protected veteran status, or any other legally protected status. #J-18808-Ljbffr Antenna Research Associates, Inc.