As a Security Engineer on our team, you will operate and maintain network security infrastructure utilized by a team of cybersecurity analysts in support of 24x7x365 mission-critical operations.

Primary Responsibilities:

• Work with government counterparts, contractors, and internal team members to deploy and manage policies, rules, and signature sets on cybersecurity capabilities
• Manage high-priority tasks and outages
• Maintain, develop, and improve Security Infrastructure standard operating procedures and tactics, techniques, and procedures (TTPs)
• Maintain complete and current network and elevation diagrams for all managed security equipment
• Coordinate and comply with applicable change control boards and corresponding processes
• Advise and strategize with government and program leadership on ways to improve the security infrastructure, requiring multi-dimensional problem solving and ingenuity with impact on multiple aspects of the mission
• Provide briefings to program/project leadership, government leadership, and other internal stakeholders on security infrastructure status, updates/patches, issues, and/or upgrades
• Operate and maintain cybersecurity capabilities to include IDS/IPS/Netflow/SIEM/Snort/Linux/Virtualization etc
• Ensure Compliance standards

Required Clearance and Certifications:

• Must have an active DoD TS/SCI clearance
• Must have DoD 8570 IAT II or higher certification (Security+ CE or equivalent) prior to start
• Must obtain a DOD-8570 CSSP Infrastructure Support certification within 6 months of start

Required Qualifications:

• Bachelor's degree and 8+ years of professional experience; additional military service and/or relevant work experience may be considered lieu of a degree

• 2+ years of technical experience deploying and maintaining cybersecurity tools, especially IDS/IPS capabilities

• Demonstrated experience with configuring, maintaining, and troubleshooting cybersecurity infrastructure and capabilities.

• Demonstrated knowledge of network traffic and communications, including known ports and services.

• Hands-on experience with the Windows and Linux operating system and their respective command line interfaces and scripting shells

• Knowledgeable in Cloud Based Internet Isolation (CBII) technologies with proven experience in designing, implementing, and managing solutions.

• Must have an active TS/SCI clearance

Preferred Qualifications:

• Experience with automation and orchestration frameworks (ex. Ansible, Puppet, Chef)

• Deep technical understanding of core current cybersecurity technologies as well as emerging capabilities

• Hands-on experience with the broader security ecosystem, major cloud platforms (AWS, Azure), and Infrastructure-as-Code tools.

• Demonstrated understanding of the life cycle of cybersecurity threats (internal and external), attacks, attack vectors and methods of exploitation with an understanding of intrusion set TTPs

• Motivated self-starter with strong written and verbal communication skills, and the ability to create complex technical reports on analytic findings

• Familiarity or experience in Intelligence Driven Defense, Cyber Kill Chain methodology, and/or MITRE ATT&CK framework

• Prior hands-on experience as a SOC analyst

About our Program:

Through the J6 Penetration Handling, Incident, System Health (PHISH) support services task order on the GSM-O contract, we provide IT products, services and solutions to the Pentagon and other DoD offices and agencies for them to meet mission and business requirements. Our Cybersecurity team performs cyber defensive actions in support of J6 to prevent, detect, respond and recover from adversarial activities.

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares.

Original Posting:

February 19, 2026

For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.

Pay Range:

Pay Range $107,900.00 - $195,050.00

The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.