MANTECH seeks a motivated, career and customer-oriented Senior Information System Security Engineer (ISSE) to join our team in Huntsville, AL.

Responsibilities include, but are not limited to:

• Define and implement cybersecurity requirements, architectures, and secure system designs across information systems and network environments
• Design, develop, and integrate security solutions, including Cross Domain Solutions (CDS), to support secure data flow and system interoperability
• Implement network security controls and countermeasures to ensure confidentiality, integrity, availability, authentication, and non-repudiation
• Identify, assess, and mitigate system and network vulnerabilities, recommending enhancements to strengthen overall security posture
• Maintain and track vulnerability data, POA&Ms, and remediation activities using GRC and enterprise tracking tools
• Lead stakeholder engagement through office hours, guidance, and updated procedures to support vulnerability management and compliance efforts
• Provide rapid response to data calls, RFIs, and leadership inquiries, including escalation and reporting of high-risk or non-compliant remediation actions

Minimum Qualifications:

• Must meet one of the following levels of experience: A high school diploma/GED and 14 years’ experience, an Associate’s degree and 10 years’ experience, a Bachelors degree and 8 years’ experience, or a Master’s and 6 years’ experience.
• Hold at least one of the following certifications: Certified Information Systems Security Professional (CISSP) (or Associate), CompTIA Advanced Security Practitioner (CASP) CE, Certified Secure Software Lifecycle Professional (CSSLP), CISSP- Information System Security Engineering Professional (ISSEP), Certified Information Security Manager (CISM), or CISSP- Information System Security Architecture Professional (ISSAP).
• Familiarity with the use and operation of security tools including: Tenable Nessus and/or Security Center, IBM Guardium, HP WeblInspect, Network Mapper (NMAP), and/or similar applications.
• Working knowledge of the National Institute of Standards and Technology (NIST) Risk Management Framework (RMF) and ATO processes.
• Experience with vulnerability management programs, including identification, tracking, and remediation of CVEs and Known Exploited Vulnerabilities (KEVs).
• Knowledge of federal cybersecurity directives and frameworks, including CISA Emergency Directives (EDs), Binding Operational Directives (BODs), and DOJ Vulnerability Patch Requirements (VPRs).
• Experience with Risk Management Framework (RMF), POA&M tracking, and governance, risk, and compliance (GRC) tools.

Preferred Qualifications:

• Degree in Computer Science, Cybersecurity, or other cyber discipline.
• Ability to operate in high-tempo environments with rapid response requirements and strict deadlines.
• Strong organizational and process improvement skills to support reporting, tracking, and compliance initiatives.

Security Clearance Requirements:

• Must have an active TOP SECRET security clearance and be willing and able to obtain SCI eligibility prior to start.
• Selected candidate must be willing to undergo a Polygraph.

Physical Requirements:

• Must be able to remain in a stationary position 50%
• Needs to occasionally move about inside the office to access file cabinets, office machinery, etc.
• Constantly operates a computer and other office productivity machinery, such as a calculator, copy machine and computer printer
• Often positions self to maintain computers in the lab, including under the desks and in the server closet
• Frequently communicates with co-workers, management and customers, which may involve delivering presentations. Must be able to exchange accurate information in these situations