Computer Network Defense (CND) Security Engineer

Computer Network Defense (CND) Security Engineer

Suitland, MD

Leidos is hiring a Computer Network Defense (CND) Security Engineer to join our team in Suitland, MD. In this role, you will help protect critical Department of Defense networks by monitoring and analyzing security events, investigating cyber threats, performing vulnerability management activities, and supporting advanced cybersecurity technologies across Windows, Linux, and VMware environments. This is an opportunity to work on mission critical systems while collaborating with a highly skilled cyber team.

Primary Responsibilities

• Monitor and analyze security events using Trellix ePO, Splunk, Palo Alto, and RSA.
• Investigate endpoint security alerts, including malware, rogue systems, and removable media events.
• Build dashboards, perform ACAS scans, and assist with vulnerability remediation efforts.
• Apply STIGs, perform system patching, and manage SCAP scans.
• Contribute to RMF documentation and maintain system and network diagrams.

Basic Qualifications

• Bachelor's degree with 8+ years of experience, or a Master's degree with 6+ years of experience. Additional relevant experience or certifications may be considered in lieu of a degree.
• Active TS/SCI clearance (in DISS).
• Active IAT Level II certification (CompTIA Security+ CE preferred).
• Linux administration experience, specifically with Red Hat Enterprise Linux (RHEL).
• 3+ years of Computer Network Defense (CND) experience.
• Experience administering enterprise scale vulnerability management systems, including deploying multi scanner architectures with Tenable Security Center (Tenable.sc) and Nessus Manager.
• Experience managing credentialed scans, performing offline plugin updates in air gapped environments, and deploying Nessus Agents at scale across diverse endpoints.
• Hands on experience with Splunk, Trellix ePO, ACAS, and RMF.

Preferred Qualifications

• Experience with VMware ESXi.
• Experience with ACAS and Nessus.

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.

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.

About Leidos

Leidos is an industry and technology leader serving government and commercial customers with smarter, more efficient digital and mission innovations. Headquartered in Reston, Virginia, with 47,000 global employees, Leidos reported annual revenues of approximately $16.7 billion for the fiscal year ended January 3, 2025. For more information, visit

Pay and Benefits

Pay and benefits are fundamental to any career decision. That's why we craft compensation packages that reflect the importance of the work we do for our customers. Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement. More details are available at

Commitment to Non-Discrimination

All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider for employment qualified applicants with criminal histories consistent with relevant laws.