Computer Network Defense Analyst

Leidos LLC; Arlington (VA); On-site; USD 70,000 - 126,000; Full time

Benefits offered by this job

Health and Wellness programs

Income Protection

Paid Leave

Retirement

Job summary

Leidos is seeking a Cyber Network Defense Analyst in Arlington, VA, to join the CESO team. The role focuses on detecting and responding to cyber threats in a 24x7 secure cloud migration environment, with heavy emphasis on collaboration across infrastructure and application teams.

You will work on incident detection, monitoring, and threat analysis, while documenting findings and coordinating with customers to improve CESO processes and security posture.

Qualifications

• Bachelor's degree and 2+ years of related experience; additional experience may be considered in lieu of degree.
• Active TS/SCI security clearance required for this position.
• DoDD 8140 IAT Level II (or Level III) certification (e.g., Security+ CE).
• Strong computing systems knowledge with Windows, Red Hat, Cloud (AWS, Azure), and networking, including IDS/IPS and firewalls.
• Experience implementing application/hardware security settings using vendor and DISA best practices.
• Candidate may be asked to obtain a CI Polygraph in the future.

Responsibilities

• Perform computer network incident detection and response to identify threats to the CESO enterprise.
• Monitor security tools for malicious activity and develop mitigation recommendations.
• Document events and analysis in a ticketing system with clear technical writing.
• Maintain regular customer interaction and address issues with minimal supervision.
• Influence team performance by improving CESO processes and procedures.
• Ensure timely system checks and complete documentation.

Skills

Networking

Windows

Red Hat

Cloud (AWS, Azure)

Security concepts

IAT Level II/III

Education

Bachelor's degree

Tools

Splunk

Elastic

IDS/IPS

Job description

We are currently seeking a Cyber Network Defense Analyst to join the Compartmented Enterprise Services Office (CESO) effort. This program is establishing a modern secure web service (SWS) operation as part of a state-of-the-art, highly automated platform capable of supporting a rapidly expanding customer population.

Our team supports CESO's mission to protect networked systems and services from cyber threats as CESO migrates to a high-security cloud environment, operating as a 24x7, mission-critical function providing network defense, monitoring, and incident response services.

We are looking for a self-starter capable of independently performing daily tasks while also working well within a team that requires significant coordination and communication.

This position is based in Arlington, VA and is 100% on-site. Requires a TS/SCI US Government Security Clearance to start.

Original Posting

Original Posting: September 22, 2026

Primary Responsibilities

• Perform computer network incident detection and response activities to detect, correlate, identify, and characterize anomalous activity indicative of threats to the CESO enterprise.
• Monitor security tools and applications for possible malicious activity, investigate associated alerts or indicators, and develop recommendations for a course of action, including mitigation strategies as required.
• Document each event and its associated analysis in a ticketing system with clear, accurate technical writing so it can be reviewed and acted on appropriately.
• Maintain regular face-to-face interaction with the customer; handle issues when they are raised by the customer with little or no supervision.
• Positively influence team performance by improving CESO processes and procedures.
• Ensure system checks are performed in a timely manner and that documentation is complete and accurate.
• Assist senior analysts and/or managers with forecasting and modeling current threats.
• Develop a strong rapport with the customer and serve as a trustworthy network defense analyst.
• Collaborate with infrastructure, storage, database, and application teams to align network defense monitoring with CESO's operational requirements as the program transitions to its secure cloud environment.

Basic Qualifications

• Bachelor's degree and 2+ years of related experience; additional experience, education, or training may be considered in lieu of degree.
• Active TS/SCI security clearance required for this position.
• DoDD 8140 IAT Level II (or Level III) certification (e.g., Security+ CE).
• Strong computing systems knowledge with Windows, Red Hat, Cloud (AWS, Azure), and particularly networking, including communication protocols and familiarity with common security elements such as IDS/IPS systems and firewalls.
• Experience with implementing application/hardware security settings using vendor and DISA best business practices.
• Candidate may be asked to obtain a CI Polygraph in the future.

Preferred Qualifications

• Prior CND experience, ideally within a large enterprise or DoD/IC program environment.
• Experience monitoring intrusion detection and computer network defense appliances, applications, and analyzing associated alerts.
• Experience documenting analysis and providing response recommendations in a ticketing/case management system.
• Experience reviewing system logs manually and using automatic SIEMs tools (e.g., SPLUNK, Elastic) and performing network log analysis.
• Prior experience with DISA and DISA's support to mission partners.
• An Understanding of disaster recovery and business continuity concepts as they apply to secure cloud migrations.

Pay and Benefits

Pay Range: $69,550.00 - $125,725.00

Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement.

• competitive compensation
• Health and Wellness programs
• Income Protection
• Paid Leave
• Retirement

More details are available here.

For more information, visit www.Leidos.com.

EEO & Diversity

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.