1784 - Network Security Engineer III

Sigma Defense•San Diego, CA

9d•$120,000 - $150,000

About The Position

Sigma Defense is seeking a Network Security Engineer III to support cybersecurity policy enforcement and security engineering across CANES environments. The role applies DoD STIGs, RMF, and NIST SP 800-53 requirements and uses tools including ACAS, Trellix ESS, NetIQ Sentinel, and Splunk. It includes hands-on system hardening, vulnerability management, and configuration automation using GitLab, GitHub, and Spork/Spork+. The engineer will support CANES system security through vulnerability remediation, platform hardening, patching, scanning, log analysis, incident response coordination, documentation, and test and installation support. Candidates must be U.S. citizens and hold or be able to obtain an active Secret clearance or higher.

Requirements

5–10 years of experience.
Must be a U.S. citizen.
Bachelor's degree from an accredited college or university.
Security+ CE or CISSP certification.
At least one operating system or platform certification in Linux, Windows, VMware, or Cisco.
Must possess or be able to obtain an active Secret security clearance or higher.
Experience engineering ACAS, rather than only using it.
Trellix ESS engineering experience, rather than administration experience.

Nice To Haves

RHEL administration expertise, with RHEL 7+ identified as ideal.
Windows administration expertise, with Windows Server 2019/2020 through 2025+ identified.
Experience with SIEM/SOAR platforms; Sentinel and Splunk experience is preferred.

Responsibilities

Implement and enforce DoD cybersecurity policies, including STIGs, RMF, and NIST SP 800-53, across CANES systems.
Design, develop, implement, and troubleshoot solutions for vulnerabilities within the CANES system.
Lead efforts to harden Windows and Linux systems, applications, network devices, and other hardware in the CANES environment.
Assist with IAVM compliance, log analysis, and audit-readiness tasks.
Perform patch management and system scanning, and coordinate incident response.
Maintain system documentation, cybersecurity artifacts, and baseline reports.
Support system validation during test events, site assessments, and production installations.
Design, develop, and automate configurations for RHEL, Windows, SIEM/SOAR, ACAS, and Trellix ESS platforms.
Submit configuration updates through GitLab/GitHub and Spork/Spork+.