Senior Information Systems Security Engineer

General information

Requisition #

R70349

Locations

USA-DC-Washington

Posting Date

09/02/2026

Security Clearance Required

TS/SCI

Remote Type

Onsite

Time Type

Full time

Description & Requirements

Unlock the secrets of intelligence with MANTECH! Join a dynamic team at the forefront of national security, providing advanced solutions to government intelligence agencies. Since 1968, we've been solving the toughest challenges with groundbreaking tech. Explore thrilling projects in Digital Transformation, Cybersecurity, IT, Data Analytics and Software Development. Elevate your career and make a difference. Your adventure begins now-unleash your potential with MANTECH!

• This is for a future opportunity*

MANTECH seeks a motivated, career and customer-oriented Senior Information Systems Security Engineer (ISSE) to join our team in Washington, D.C. This is an onsite position.

The Information Systems Security Engineer (ISSE) will leverage their strong technical background and knowledge to support accreditation efforts, to include responding to/implementing/documenting required controls, and completing required tasks/actions.

Responsibilities include but are not limited to:

• Designing secure architectures, hardware, operating systems, and software applications to ensure cybersecurity requirements are adequately addressed for the IS and Network Environment.
• Designing, developing, and implementing network security measures and specific countermeasures that provide confidentiality, integrity, availability, authentication, and non-repudiation.
• Integrating and implementing security protocols with Cross Domain Solutions (CDS) for use within the IS and Network Environment.
• Developing interface specifications and approaches to mitigate vulnerabilities while recommending changes to network system components as needed.
• Ensuring that network system designs support the seamless incorporation of directed cybersecurity vulnerability solutions.
• Documenting responses to required controls and maintaining a robust library of documentation to successfully navigate the Sponsor's accreditation process.
• Working with management, internal teams, and stakeholders to ensure complete and functioning systems that meet all mission requirements.

Minimum Qualifications:

• Bachelor's degree or equivalent (6 additional years of experience) in computer science, business management, or an IT-related discipline.
• 10 + years of related information systems security experience, or a Master's degree with 7+ years of experience.
• Posession of one or more relevant industry certifications, such as CCISO, CISA, CISM, CISSP, CISSP-ISSEP, CySA+, GSLC, GSNA, CCNP Enterprise, CISSP-ISSAP, GCIA, GDSA, or GICSP.
• 4 + years of focused experience in one or more of the following: computer network penetration testing and techniques; computer evidence seizure, computer forensic analysis, and data recovery; computer intrusion analysis and incident response, intrusion detection; computer network surveillance and monitoring; network protocols, network devices, multiple operating systems, and secure architectures.
• Significant experience navigating technical accreditation processes and creating Assessment & Authorization (A&A) Body of Evidence (BOE) documentation.
• Familiarity operating standard security and discovery tools including Tenable Nessus, Security Center, IBM Guardium, HP WebInspect, and Network Mapper (NMAP).

Preferred Qualifications:

• Hands-on experience utilizing cyber risk and compliance automation tools.
• Self-starter with excellent interpersonal skills who is able to work across teams, organize boards, and drive change throughout an organization.

Clearance Requirements:

• Must have a current/active TS/SCI.
• Ability to obtain and maintain a polygraph.

Physical Requirements:

• Must be able to remain in a stationary position 50% of the time.
• Needs to occasionally move about inside the office to access file cabinets, office machinery, and other equipment.
• Frequently communicates with co-workers, management, and customers, which may involve delivering presentations.
• Must be able to exchange accurate information in these situations.

The projected compensation range for this position is $141,500.00-$236,000.00. There are differentiating factors that can impact a final salary/hourly rate, including, but not limited to, Contract Wage Determination, relevant work experience, skills and competencies that align to the specified role, geographic location (For Remote Opportunities), education and certifications as well as Federal Government Contract Labor categories. In addition, MANTECH invests in its employees beyond just compensation. MANTECH's benefits offerings include, dependent upon position, Health Insurance, Life Insurance, Paid Time Off, Holiday Pay, short-term and long-term Disability, Retirement and Savings, Learning and Development opportunities, wellness programs as well as other optional benefit elections.

MANTECH considers all qualified applicants for employment without regard to disability or veteran status or any other status protected under any federal, state, or local law or regulation.

If you need a reasonable accommodation to apply for a position with MANTECH, please email us at careers@mantech.com and provide your name and contact information.