Information Systems Security Engineer (ISSE)

Vosper Thornycroft Group; Chantilly (VA); On-site; USD 90,000 - 130,000; Full time

Job summary

A leading technology firm in Virginia seeks a skilled Information Systems Security Engineer to design and implement security controls across enterprise systems. This role involves ensuring compliance with security policies, conducting vulnerability scans, and supporting risk management activities. Ideal candidates will have over 5 years of experience in information security, a Bachelor's degree related to Cybersecurity, and active TS/SCI clearance. You will work closely with diverse teams to enhance system security and manage security tools effectively.

Qualifications

• 5+ years of experience in information security, primarily in system security engineering.
• Hands-on experience with the Risk Management Framework and NIST controls.
• Knowledge of operating systems such as Windows and Linux.

Responsibilities

• Design, implement, and maintain security controls for information systems and networks.
• Support the Risk Management Framework lifecycle.
• Conduct security assessments and vulnerability scans.

Skills

Active TS/SCI with Polygraph

System security engineering

Risk Management Framework (RMF)

NIST 800-53 controls

Vulnerability scanning tools

Network security principles

Education

Bachelor’s degree in Cybersecurity, IT or related field

Tools

SIEM

ACAS

Nessus

Job description

Overview

We are seeking a highly skilled Information Systems Security Engineer (ISSE) to design, implement, and maintain security controls across enterprise systems and networks. This role ensures systems are compliant with security requirements while supporting mission‑critical operations. The ISSE will work closely with system owners, engineers, and cybersecurity teams to integrate security throughout the system lifecycle.

What will you do?

• Design, implement, and maintain security controls for information systems and networks
• Support the Risk Management Framework (RMF) lifecycle, including system categorization, control selection, implementation, assessment, and authorization
• Conduct security assessments, vulnerability scans, and risk analysis
• Develop and maintain system security documentation (SSP, POA&M, SAR, etc.)
• Ensure systems comply with NIST, RMF, and organizational security policies
• Collaborate with ISSOs, system administrators, and developers to remediate vulnerabilities
• Support continuous monitoring and incident response activities
• Implement and manage security tools (SIEM, IDS/IPS, endpoint protection, etc.)
• Provide technical guidance on secure system architecture and design
• Stay current on emerging threats, vulnerabilities, and security technologies

Do you have what it takes?

• Active TS/SCI with Polygraph required.
• Bachelor’s degree in Cybersecurity, Information Technology, Computer Science, or related field (or equivalent experience)
• 5+ years of experience in information security, with focus on system security engineering
• Hands‑on experience with RMF and NIST 800‑53 controls
• Experience developing and maintaining A&A documentation (SSP, POA&M, ATO packages)
• Knowledge of operating systems (Windows, Linux) and network security principles
• Experience with vulnerability scanning tools (ACAS, Nessus, or similar)
• Familiarity with security tools such as SIEM, firewalls, and endpoint protection
• Understanding of encryption, identity management, and access control mechanisms