Quarantine Release/Systems Security Engineer

Systems Security Engineer (Cybersecurity / Quarantine Release)

Location: Dahlgren, VA (Hybrid – 3 days onsite / 2 remote)

Employment Type: Contract-to-Hire / Full-Time

Clearance: Active Secret required (Top Secret preferred)

Certification: DoD 8570 IAT Level II

Salary Range: $65,000 – $80,000

About Apex Systems

Apex Systems is a leading technology services firm that provides innovative solutions to government and commercial clients. We specialize in delivering high-quality talent and expertise across cybersecurity, infrastructure, cloud, and digital transformation initiatives.

Overview

Apex Systems is seeking a Systems Security Engineer to support a DoD client in Dahlgren, VA. This role is focused on vulnerability management, system hardening, and cyber defense operations within a secure enterprise environment.

The ideal candidate will have hands-on experience with DoD cybersecurity tools, network security principles, and risk mitigation strategies, and will play a key role in strengthening the organization's overall security posture.

Key Responsibilities

• Conduct vulnerability scans and identify security weaknesses across systems, applications, and networks
• Utilize DoD security tools such as ACAS, HBSS, and related platforms
• Perform application vulnerability assessments and analyze configuration data to identify systemic risks
• Apply cybersecurity principles (confidentiality, integrity, availability, authentication, non-repudiation)
• Implement system, network, and OS hardening techniques (e.g., least privilege, segmentation, logging)
• Troubleshoot and resolve cyber defense infrastructure issues and anomalies
• Perform impact and risk assessments to support remediation efforts
• Analyze threat environments and provide actionable insights to improve security posture
• Implement and maintain access controls, VPNs, and encryption protocols
• Support malware defense using IDS/IPS, anti-malware, and endpoint security tools
• Perform other duties as assigned

Required Qualifications

• Bachelor's degree or equivalent experience
• 2–5 years of relevant cybersecurity / systems security experience
• Active DoD 8570 IAT Level II certification (e.g., Security+)
• Active Secret clearance required (Top Secret preferred)
• Strong knowledge of:
  • Networking protocols (TCP/IP, DNS, DHCP)
  • Network security methodologies and architecture (defense-in-depth, zero trust)
  • System, network, and OS hardening techniques
  • IDS/IPS tools and vulnerability management
  • Application security and common vulnerabilities
• Experience supporting one or more of the following:
  • Windows
  • Linux/Unix
  • Mobile platforms (iOS/Android)

Preferred Qualifications

• Knowledge of cyber threats, vulnerabilities, and attack vectors
• Experience with network traffic analysis and monitoring
• Familiarity with Identity and Access Management (IAM) (PKI, SAML, OAuth, etc.)
• Experience with RMF / NIST 800-53 frameworks
• Understanding of wireless and transmission technologies (Wi-Fi, RFID, Bluetooth, VoIP)
• Ability to analyze and respond to various attack types (insider, passive, active, etc.)

Physical Requirements

• Ability to stand or walk for extended periods
• Ability to lift up to 10–20 lbs
• Occasional bending, twisting, or squatting

Additional Details

• Hybrid schedule: 3 days onsite in Dahlgren, VA
• U.S. Citizenship required to support clearance