Information System Security Officer (ISSO)

Location:

Onsite – Customer Site

Clearance:

Secret (Required)

Employment Type:

Contract / Full-Time (based on engagement)

Position Overview

We are seeking a highly motivated and experienced

Information System Security Officer (ISSO)

to support the security posture of a mission-critical Department of Defense (DoD) information system. This role works closely with the Information System Security Manager (ISSM) and Information System Owner (ISO) and is responsible for the

day-to-day security operations, compliance, and risk management

of assigned systems.

Key Responsibilities

- Support certification and authorization (C&A / ATO) activities in accordance with

DoD RMF and NIST standards

- Define, create, and maintain system security documentation

- Assess security impacts related to system modifications and technology changes

- Develop, implement, and maintain information security policies, procedures, and standards

- Conduct

STIG implementation, ACAS (Tenable/Nessus) scans

, and vulnerability remediation

- Monitor security logs and alerts; respond to security incidents

- Upload and manage

STIG and ACAS scan results

- Manage

Plan of Action and Milestones (POA&M)

activities

- Maintain security documentation including risk assessments, incident reports, and policies

- Collaborate with IT and system stakeholders throughout the system development lifecycle

- Participate in internal and external security audits and assessments

- Support disaster recovery and business continuity planning

- Stay current with evolving cybersecurity threats, vulnerabilities, and regulatory requirements

Required Qualifications

- Bachelor’s degree in Computer Science, Information Systems, or a related field

(or equivalent years of experience)

- Minimum 7 years of information security experience

(or 3+ years with BA/BS)

- Active or current Secret security clearance

- IAM Level III certification

in accordance with DoD 8140

(CISSP, CISM, or GIAC/GSLC)

- Strong knowledge of

NIST, RMF, and DoD cybersecurity requirements

- Hands-on experience with

STIGs, ACAS, eMASS

- Excellent analytical, problem-solving, and communication skills

- Ability to work independently and as part of a team

Preferred Qualifications

- Experience with

Windows Server 2016/2019 or newer

- Active Directory, Group Policy, DNS, Radius

- VMware or Hyper-V virtual environments

- Familiarity with

SQL Server

- Experience with Microsoft Endpoint Security

- Experience applying patches, updates, and DISA STIGs

- Familiarity with

eMASS workflows

- Experience with Cyber Security Service Provider (CSSP) environments

- DoD Cyber Protection Team experience

Tools & Technologies

- ACAS (Tenable / Nessus)

- DISA STIG

- eMASS

- Event monitoring and vulnerability management tools

- Microsoft Server and security technologies

Work Environment

- Onsite role

at a secure customer location

- Mission-critical DoD system support

- Collaboration with cross-functional technical and security teams

About Seneca Resources 

At Seneca Resources, we are more than just a staffing and consulting firm, we are a trusted career partner. With offices across the U.S. and clients ranging from Fortune 500 companies to government organizations, we provide opportunities that help professionals grow their careers while making an impact.

When you work with Seneca, you’re choosing a company that invests in your success, celebrates your achievements, and connects you to meaningful work with leading organizations nationwide. We take the time to understand your goals and match you with roles that align with your skills and career path. Our consultants and contractors enjoy competitive pay, comprehensive health, dental, and vision coverage, 401(k) retirement plans, and the support of a dedicated team who will advocate for you every step of the way.

Seneca Resources is proud to be an Equal Opportunity Employer, committed to fostering a diverse and inclusive workplace where all qualified individuals are encouraged to apply.