Cyber Security Engineer: Network Defense (TS/SCI)

CACI International Inc; St. Louis (MO); On-site; USD 75,000 - 158,000; Full time

Job summary

CACI is seeking a Cyber Security Engineer for the NSS Tools team. The role focuses on developing, deploying, and maintaining cybersecurity tools to defend NGA networks across multiple locations globally. Responsibilities include architecture documentation, tool deployment, and leadership briefings.

The candidate will work with Linux environments, log analysis, and DoW/IC standard practices, with opportunities to advance security capabilities and contribute to mission-critical operations.

Qualifications

• Active TS/SCI clearance required.
• Ability to obtain/maintain CI polygraph.
• DOD 8570 IAT II certs (Security+, CySA+, etc.).
• DOD 8570 CSSP Infrastructure certs (CEH, CySA+, etc.).
• Willingness to work weekends/evenings as needed.
• Ability to work independently with minimal supervision.

Responsibilities

• Design, implement, and deliver defensive cybersecurity solutions for on‑premise and cloud environments.
• Deploy, configure, and maintain network security tools and ensure core services function per design.
• Develop and maintain network architecture diagrams, inventories, and licensing status.
• Provide written reports and oral briefings to contract and government leadership.
• Coordinate issues with stakeholders to ensure task completeness and customer satisfaction.
• Evaluate and report on new/emerging network security technologies to enhance capacity and reliability.
• Evaluate configuration changes and upgrades to address performance and standardization.
• Apply networking protocol knowledge and use troubleshooting tools to diagnose issues.

Skills

Security clearance TS/SCI

CI polygraph

DOD 8570 IAT II

DOD 8570 CSSP Infrastructure

Weekend/evening hours

Independence

DoW PKI Kerberos LDAP AD SAML OAuth

Education

Bachelor’s degree in CS / IT / CE / EE or related

Tools

NDR platforms (VectraAI)

NDR platforms (Extrahop)

NDR platforms (Darktrace)

NDR platforms (Corelight)

NDR platforms (Cisco Firepower)

NDR platforms (Trellix NX)

Packet broker platforms (Gigamon)

Packet broker platforms (Ixia)

Packet broker platforms (Garland)

Packet capture platforms (NetWitness)

Packet capture platforms (Axellio)

Packet capture platforms (Endace)

Email security platforms (Trellix EX)

Email security platforms (Cisco Secure Email Gateway)

Email security platforms (Ironport)

Email security platforms (Proofpoint)

Email security platforms (Abnormal)

Job description

CACI is seeking a Cyber Security Engineer for the NSS Tools team. The role focuses on developing, deploying, and maintaining cybersecurity tools to defend NGA networks across multiple locations globally. Responsibilities include architecture documentation, tool deployment, and leadership briefings.

The candidate will work with Linux environments, log analysis, and DoW/IC standard practices, with opportunities to advance security capabilities and contribute to mission-critical operations.