Senior Cyber Security Engineer

CACI International Inc; Chantilly (VA); On-site; USD 104,000 - 218,000; Full time

Job summary

CACI International Inc in Chantilly, VA seeks a Senior Cyber Security Engineer to protect mission‑critical environments. You will support cybersecurity applications, automate workflows, and strengthen system security across the enterprise.

Responsibilities include configuring and maintaining security tools, developing scan policies for Tenable Nessus with ServiceNow integration, and delivering Tier 2/3 support while contributing to A&A artifacts and incident response efforts.

Qualifications

• Active TS/SCI clearance with polygraph.
• Bachelor’s degree or 4+ years of additional relevant experience.
• 5+ years of experience with cybersecurity tools in an enterprise environment.
• Hands-on with Tenable products and enterprise vulnerability scanning.
• Strong Windows and Linux administration and network security knowledge.
• IAT Level II certification or ability to obtain within 30 days.

Responsibilities

• Provide engineering support and system administration for cybersecurity applications.
• Develop, customize, and manage scan policies, dashboards, and reports for Nessus and ServiceNow.
• Deliver Tier 2/3 support and ensure compliance with policies and TASKORDs.
• Troubleshoot vulnerability scanning issues via multiple channels.
• Support A&A activities by updating documentation and security artifacts.

Skills

TS/SCI with polygraph

Windows administration

Linux administration

TCP/IP networking

Defence-in-depth

Vulnerability scanning

Automation scripting

Communication skills

A&A documentation

Incident response

Team collaboration

Education

Bachelor’s degree or equivalent

Tools

Tenable Nessus

ServiceNow

Job description

Job Title: Senior Cyber Security EngineerJob Category: Information TechnologyTime Type: Full timeMinimum Clearance Required to Start: TS/SCI with PolygraphEmployee Type: RegularPercentage of Travel Required: Up to 10%Type of Travel: Local* * *The Opportunity:We are seeking a Senior Cyber Security Engineer to join our team in Chantilly, VA. In this role, you will help protect mission‑critical enterprise environments by supporting specialized cybersecurity applications, advancing system security, and enhancing operational efficiency. You will work closely with technical teams and customers to strengthen cybersecurity capabilities, automate workflows, and ensure secure, reliable operations across the enterprise. If you thrive in a dynamic environment and enjoy solving complex challenges, this is an exciting opportunity to make a meaningful impact.Responsibilities:Provide engineering support and system administration for cybersecurity applications, including installation, configuration, maintenance, patching, and backup/restore.Develop, customize, and manage scan policies, audit files, scan jobs, dashboards, reports, and related content for tools such as Tenable Nessus and ServiceNow integrations.Deliver Tier 2 and Tier 3 support for cybersecurity technologies and ensure compliance with customer policies, procedures, and TASKORDs.Troubleshoot vulnerability scanning issues and provide responsive support via phone, email, and messaging platforms.Identify opportunities for process automation and integrate scripted solutions to streamline repetitive tasks and metrics collection.Support Assessment & Authorization (A&A) activities by updating documentation, preparing security artifacts, and resolving technical conflicts.Analyze policies, customer feedback, and operational workflows to recommend enhancements that improve efficiency and cybersecurity posture.Qualifications:Required:Active TS/SCI clearance with polygraph.Bachelor’s degree or 4+ years of additional relevant experience.5+ years of experience working with cybersecurity tools in an enterprise environment.Hands‑on experience with Tenable products and enterprise vulnerability scanning operations.Strong knowledge of Windows and Linux administration, operating system hardening, TCP/IP networking, and core network security concepts.Demonstrated expertise in enterprise scanning, continuous monitoring, host/network defense, and intrusion detection.Ability to translate functional cybersecurity needs into technical requirements and apply architectural principles such as defense‑in‑depth and resilience.Excellent communication, organization, troubleshooting, and customer‑support skills.Active IAT Level II certification, or the ability to obtain it within 30 days of hire.Desired:Experience with AWS services and ServiceNow.Familiarity with federal cybersecurity frameworks such as NIST SP 800‑37 (RMF) and NIST SP 800‑137 (Continuous Monitoring).Experience developing automation and scripting solutions to support workflow optimization.Ability to perform effectively in a fast‑paced environment while managing multiple priorities.Strong collaboration skills with the ability to work independently or as part of a team.This position is contingent on funding and may not be filled immediately. However, this position is representative of positions within CACI that are consistently available. Individuals who apply may also be considered for other positions at CACI.What You Can Expect: A culture of integrity.At CACI, we place character and innovation at the center of everything we do. As a valued team member, you’ll be part of a high-performing group dedicated to our customer’s missions and driven by a higher purpose – to ensure the safety of our nation.An environment of trust.CACI values the unique contributions that every employee brings to our company and our customers - every day. You’ll have the autonomy to take the time you need through a unique flexible time off benefit and have access to robust learning resources to make your ambitions a reality.A focus on continuous growth.Together, we will advance our nation's most critical missions, build on our lengthy track record of business success, and find opportunities to break new ground — in your career and in our legacy.Pay Range :There are a host of factors that can influence final salary including, but not limited to, geographic location, Federal Government contract labor categories and contract wage rates, relevant prior work experience, specific skills and competencies, education, and certifications. Our employees value the flexibility at CACI that allows them to balance quality work and their personal lives. We offer competitive compensation, benefits and learning and development opportunities. Our broad and competitive mix of benefits options is designed to support and protect employees and their families. At CACI, you will receive comprehensive benefits such as; healthcare, wellness, financial, retirement, family support, continuing education, and time off benefits.The proposed salary range for this position is:$103,800 - $218,100CACI is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, pregnancy, sexual orientation, age, national origin, disability, status as a protected veteran, or any other protected characteristic.