Senior Information System Security Engineer | TS/SCI Poly

Acclaim Technical Services, Inc.; Chantilly (VA); On-site; USD 120,000 - 160,000; Full time

Job summary

Acclaim Technical Services, Inc. in Chantilly, VA is seeking an Information System Security Engineer (ISSE) with TS/SCI clearance and polygraph to support data and systems integration and A&A activities. You will design security controls, perform vulnerability assessments, and liaise with ISSMs to resolve issues in a multi‑enclave environment.

A bachelor’s degree plus 8 years of experience is required. The role focuses on ensuring compliant documentation, embedding IA systems, and coordinating

Qualifications

• Prior ISSE and Network Engineering experience on technical communications or intelligence programs.
• Bachelor's degree plus eight years of experience required.
• TS/SCI clearance with polygraph is required.

Responsibilities

• Design and embed security controls into system architectures.
• Ensure vulnerability scans run routinely and patch issues with admins/developers.
• Review A&A documentation and ensure completeness and compliance.
• Understand computer architecture, networking, OS, and network security.
• Collaborate with ISSMs to resolve issues.
• Develop, implement, and integrate IA and security systems across environments.
• Review security assessments to identify vulnerabilities and non‑compliance.
• Create and review A&A Body of Evidence and feedback on content.
• Advise Sponsor customers on Lifecycle Assessment and Authorization.
• Maintain baselines and CM items, including security event monitoring policies.
• Coordinate changes through Sponsor's approval processes.
• Maintain documentation per agency regulations for each project.
• Enforce trusted interfaces among external systems and architectures.
• Use COTS/GOTS and custom tools to scan, contain, mitigate and remediate threats.
• Protect information systems from unauthorized access and disclosure.
• Recognize intrusion indicators through thorough reviews of events.

Skills

ISSE Experience

Network Engineering

Security Architecture

TS/SCI clearance

Polygraph

Education

Bachelor's Degree + 8 years

Job description

Acclaim Technical Services, Inc. in Chantilly, VA is seeking an Information System Security Engineer (ISSE) with TS/SCI clearance and polygraph to support data and systems integration and A&A activities. You will design security controls, perform vulnerability assessments, and liaise with ISSMs to resolve issues in a multi‑enclave environment.

A bachelor’s degree plus 8 years of experience is required. The role focuses on ensuring compliant documentation, embedding IA systems, and coordinating