Senior Information Systems Security Engineer (ISSE)

Apavo Corporation; Arlington (VA); On-site; USD 130,000 - 180,000; Full time

Job summary

Apavo Corporation, based in Arlington, VA, seeks a Senior Information Systems Security Engineer (ISSE) to provide expert security engineering across the system lifecycle. You will integrate RMF controls, lead A&A activities, and support authorization decisions with engineering teams and ISSOs.

You will mentor junior engineers, develop system security documentation, and coordinate with program leadership on risk mitigation while staying current on evolving threats in defense-grade environments.

Qualifications

• Bachelor's degree with 8+ years of cybersecurity experience.
• Must lead RMF/A&A processes on complex systems.
• Active TS/SCI clearance; TS/SCI eligible.
• DoD 8570/8140-compliant certification required (CISSP preferred).
• Strong knowledge of NIST RMF and NIST SP 800-53/800-37.
• Experience with vulnerability scanning, secure baselines, and hardening.
• Experience with cloud security and Zero Trust concepts.
• Effective communication with senior leadership.

Responsibilities

• Provide senior-level security engineering across the SDLC.
• Lead RMF/A&A activities and produce security artifacts.
• Conduct security control assessments and remediation strategies.
• Advise on secure design options and risk mitigation.
• Oversee continuous monitoring, vulnerability management, and patching.
• Develop BoE packages and security documentation.
• Coordinate with ISSMs, AOs, and stakeholders on approvals.
• Mentor junior security engineers and improve processes.
• Stay current on threats, vulnerabilities, and mitigations.

Skills

RMF/A&A leadership

Security engineering

Vulnerability management

Strong communication

Stakeholder leadership

Education

Bachelor's degree

DoD 8570/8140 certification

Tools

Vulnerability scanning tools

Secure configurations

Zero Trust concepts

Cloud security principles

Job description

Description

Location: Arlington, VA

Department: Cyber Security Services

Reports To: Management

FLSA Status: Full Time/Non-exempt

Apavo is at the forefront of cybersecurity, providing services to military, defense, and critical infrastructure industries. Joining the Apavo team means becoming part of a company rooted in the principles of quality, and communication. We value positive, candid interactions and the belief that everyone has valuable contributions to make. Apavo stands out for its commitment to a work-life balance and fostering a growth mindset among all team members. If you are looking to make a meaningful impact in the cybersecurity world while growing professionally in a supportive environment, Apavo is the place for you.

Job Purpose:

The Senior Information Systems Security Engineer (ISSE) provides expert-level technical security engineering support throughout the system lifecycle, ensuring information systems are designed, developed, and maintained in accordance with applicable security requirements. This role works closely with ISSOs, system owners, and engineering teams to integrate security controls into system design, lead security engineering efforts on complex initiatives, and support the Assessment and Authorization (A&A) process.

Duties & Responsibilities:

The Senior ISSE responsibilities include, but are not limited to:

• Provide senior-level security engineering support across the system development lifecycle, from requirements definition through sustainment
• Apply advanced security engineering principles to integrate controls into system design, architecture, and configuration
• Lead and support the Risk Management Framework (RMF) process, including development and review of security artifacts (SSP, SAR, POA&M, etc.)
• Conduct security control assessments and lead remediation strategies for identified vulnerabilities
• Advise system owners, ISSOs, and program leadership on secure design alternatives and risk mitigation options
• Oversee continuous monitoring activities, including vulnerability scanning, patch management, and configuration compliance
• Lead development and maintenance of system security documentation and Body of Evidence (BoE) packages
• Coordinate with ISSMs, AOs, and other stakeholders to support and defend authorization decisions
• Evaluate proposed system changes for security impact and lead security input to change management processes
• Mentor junior security engineers and contribute to team-wide process improvement
• Stay current on emerging threats, vulnerabilities, and mitigation techniques relevant to the supported environment

The Senior ISSE is expected to have additional duties as assigned in support of corporate cybersecurity services. Additional details are reviewed in accordance with company policies.

Requirements

Qualifications

• Bachelor's degree and 8+ years of relevant cybersecurity experience (or equivalent combination of education and experience)
• Demonstrated experience leading RMF/A&A processes and security engineering activities on complex systems
• Active Top Secret Clearance with the ability to obtain TS/SCI
• DoD 8570/8140-compliant certification required (e.g., CISSP required; CAP a plus)
• Strong knowledge of NIST RMF, NIST 800-53, NIST 800-37, and related frameworks
• Extensive experience with vulnerability scanning tools, secure configuration baselines, and system hardening
• Experience with cloud security principles and Zero Trust concepts
• Proven ability to communicate technical risk to both technical and non-technical stakeholders, including senior leadership
• Strong analytical, documentation, leadership, and interpersonal skills

Other:

This is typical office or administrative work, and there is no exposure to adverse environmental conditions.

This position requires sedentary work. Sedentary work is defined as: Exerting up to 10 pounds of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull or otherwise move objects, including the human body. Sedentary work involves sitting most of the time. Jobs are sedentary if walking and standing are required only occasionally, and all other sedentary criteria are met.

Apavo Corporation provides equal employment opportunities to all applicants and employees and strictly prohibits any type of harassment or discrimination in regards to race, religion, age, color, sex, disability status, national origin, genetics, sexual orientation, protected veteran status, gender expression, gender identity, or any other characteristic protected under federal, state, and/or local laws.

Consistent with the Americans with Disabilities Act (ADA), it is the policy of Apavo Corporation to provide reasonable accommodation when requested by a qualified applicant or employee with a disability, unless such accommodation would cause an undue hardship. The policy regarding requests for reasonable accommodation applies to all aspects of employment, including the application process. If reasonable accommodation is needed, please contact Apavo Human Resources at [e-mail] or 571-407-0069.

Employment with Apavo Corporation is on an at-will basis, meaning either you or the Company can terminate the employment relationship, at any time, for any or no reason, and with or without cause or notice. As an at-will employee, your employment with Apavo Corporation is not guaranteed for any length of time.