Security Engineer (TS - Cleared) - Endpoint Protection & HBSS

Job Description

Job Description

Overview

We are seeking a Senior Security Engineer to support a classified federal cybersecurity program that provides secure intelligence, collaboration, and data protection capabilities across the U.S. Government.

This position plays a critical role in safeguarding the Treasury Foreign Intelligence Network (TFIN) infrastructure — ensuring compliance, resilience, and protection of mission-critical systems in accordance with federal cybersecurity standards (FISMA, CNSS, NIST 800-53, DISA STIGs, and ICD 503).

The Security Engineer will lead enterprise endpoint protection operations, vulnerability management, and defensive cybersecurity engineering within a secure compartmented environment (SCIF).

Key Responsibilities

• Administer and maintain Trellix (formerly McAfee) ePO infrastructure: policy management, agent deployment, signature updates, and troubleshooting across all TFIN systems.
• Provide daily security oversight of enterprise systems and network components.
• Engineer, implement, and maintain endpoint protection architecture (ENS, TIE, Solidcore, DLP).
• Operate and maintain HBSS (or successor platform), Tripwire, Nessus/Retina, ArcSight, M3, and other IDS/IPS tools.
• Conduct malware analysis, indicator creation, and threat detection tuning to enhance defense posture.
• Support forensic investigations, incident response, and containment activities.
• Oversee firewall configurations, antivirus architecture, and network-level defense mechanisms.
• Perform system hardening and vulnerability remediation across endpoints and servers.
• Conduct security impact assessments and provide recommendations to the TFIN Architect and Change Control Board (CCB).
• Support PKI operations, including certificate issuance, revocation, and secure enrollment.
• Participate in Security Assessment & Authorization (A&A) processes, preparing IATT and ATO documentation.
• Review and ensure compliance with STIGs, IC SCC guidance, and Treasury security policies.
• Contribute to counterintelligence and insider threat detection efforts, including behavioral monitoring and anomaly analysis.
• Develop, maintain, and report on STIG Compliance, Vulnerability Scans, and POA&M updates as required by federal standards.

Required Qualifications

• Active Top Secret clearance with SCI eligibility.
• Minimum 5 years of hands-on experience administering Trellix/McAfee ePO and related components (ENS, TIE, Solidcore, DLP).
• Proven experience managing endpoint protection systems, antivirus architecture, and threat response.
• Strong knowledge of IDS/IPS systems, forensic analysis, and vulnerability scanning.
• Demonstrated ability to implement DISA STIGs, NIST 800-53, and IC SCC cybersecurity controls.
• Familiarity with incident response procedures, system hardening, and risk mitigation.
• Strong analytical, troubleshooting, and communication skills.

Preferred Skills

• Experience supporting federal cybersecurity or intelligence community programs in classified environments.
• Familiarity with HBSS, ArcSight, Nessus, Tripwire, and similar tools.
• Knowledge of PKI operations and certificate management.
• Experience preparing IATT/ATO packages and supporting Risk Management Framework (RMF) activities.
• Working knowledge of counterintelligence and insider threat detection concepts.
• Bachelor’s degree in Cybersecurity, Information Systems, Computer Science, or related field.
• Certifications (Preferred): Security+, CEH, CISSP, or equivalent vendor certifications in endpoint protection.

Company DescriptionTenacity Solutions, LLC (Tenacity) is a Service-Disabled Veteran Owned Small Business (SDVOSB) founded by our CEO, Gabriel Brown, CAPT, USN (Ret). Tenacity is an innovative company, leveraging talent, skill, and knowledge with cutting-edge and proven practices to deliver solutions and products that exceed customers’ requirements and surpasses their expectations. Tenacity immediately has become a leading technology and management solutions provider with a mission to advance healthcare services for specialized populations including Veterans and their families. Headquartered in North, Bethesda, Maryland (DMV), our talented resources are located across the United States. We bring diverse talent to design solutions that help customers with their greatest challenges.

Company Description

Tenacity Solutions, LLC (Tenacity) is a Service-Disabled Veteran Owned Small Business (SDVOSB) founded by our CEO, Gabriel Brown, CAPT, USN (Ret). Tenacity is an innovative company, leveraging talent, skill, and knowledge with cutting-edge and proven practices to deliver solutions and products that exceed customers’ requirements and surpasses their expectations. Tenacity immediately has become a leading technology and management solutions provider with a mission to advance healthcare services for specialized populations including Veterans and their families. Headquartered in North, Bethesda, Maryland (DMV), our talented resources are located across the United States. We bring diverse talent to design solutions that help customers with their greatest challenges.