Cyber Security Engineer, Jr.

The Opportunity:

CST is seeking a skilled Cybersecurity Engineer with hands-on experience in designing, implementing, and remediating technical cyber controls across DoD contractor and commercial environments. The ideal candidate will demonstrate expertise in Linux hardening, secure coding, and compliance with NIST standards, as well as strong documentation and communication skills.
Responsibilities:

- Design, develop, and implement technical cyber controls for security applications and infrastructure.

- Harden Linux servers (RHEL-family, Alma Linux, Ubuntu, Kali) using SELinux, firewalled, least privilege, and shell scripting.

- Apply secure coding practices in Python, including input allow listing, secrets management, and constant-time authentication checks.

- Prepare design alternatives, deployment requirements, and testing approaches for security applications.

- Assess and remediate controls derived from NIST SP 800-53 and NIST SP 800-171; track remediation through POA&Ms.

- Conduct vulnerability assessments using Tenable Nessus and prioritize findings by CVSS score and business risk.

- Monitor and investigate security alerts across Splunk, Elastic, Lima Charlie, and Sentinel One; escalate confirmed threats.

- Author technical documentation, including POA&Ms, design specifications, deployment instructions, and testing plans.

- Collaborate with development teams to integrate security controls and requirements into new and existing applications.

- Research and configure cyber controls to align with CIS Benchmarks, DISA STIG, and FIPS 140-2 guidelines.

Qualifications:
Required: 
- Technical cyber controls design and implementation.

- Linux hardening and systems-level configuration tuning.

- Secure coding practices in Python and Flask (REST APIs).

- Experience with NIST SP 800-53, NIST SP 800-171, NIST RMF, CMMC, POA&Ms, DoD requirements.

- Familiarity with CIS Benchmarks, DISA STIG, FIPS 140-2.

- Vulnerability assessment tools: Tenable Nessus, Splunk, Elastic, SentinelOne, Wireshark, Kali Linux.

- Bash and shell scripting, cron automation, PowerShell.

- Strong professional documentation and communication skills.

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: