Senior Information System Security Officer

Leidos has a new and exciting opportunity for a Senior Information System Security Officer in our National Security Sector's (NSS) Cyber & Analytics Business Area (CABA). Our talented team is at the forefront in Security Engineering, Computer Network Operations (CNO), Mission Software, Analytical Methods and Modeling, Signals Intelligence (SIGINT), and Cryptographic Key Management. At Leidos, we offer competitive benefits, including Paid Time Off, 11 paid Holidays, 401K with a 6% company match and immediate vesting, Flexible Schedules, Discounted Stock Purchase Plans, Technical Upskilling, Education and Training Support, Parental Paid Leave, and much more. Join us and make a difference in National Security! Senior Information System Security Officer (ISSO) Leidos currently has an opening for a Senior Information System Security Officer (ISSO) to work at our Annapolis Junction, MD location. The selected candidate will act as an ISSO for a large software development program which includes software maintenance and development, IT support (Network/Workstation/Server), systems integration and life cycle support, enterprise application development, network engineering, and information systems security (ISS). The candidate will work with other security professionals in developing and implementing strategies to detect and mitigate threats to information systems, protect critical data sets, and provide assessments of system and network vulnerabilities. Primary Roles and Responsibilities Provide support for implementing and enforcing information systems security policies, standards, and methodologies. Assist in the evaluation of security solutions to ensure they meet security requirements for processing multiple types of information. Assist with the Configuration Management for information system security software, hardware, and firmware. Analyze threats and develop and implement best practice methodologies for incident detection, reporting, and vulnerability remediation. Maintain records on workstations, servers, routers, firewalls, intelligent hubs, network switches, etc. to include system upgrades. Evaluate security solutions to ensure they meet security requirements for processing information. Maintain operational security posture for information systems. Provide support to the Information System Security Manager (ISSM) for maintaining the appropriate operational IA posture for a system/program/enclave. Develop and maintain documentation for Certification & Accreditation in accordance with specified policies. Develop and update system security plans and other IA documentation. Provide support for Information Assurance Vulnerability Alerts (IAVAs) management (initiating IAVA responses and system security scans, completing remediation, extending IAVA patches and security updates to designated sites, etc.). Provide CM for security-relevant information system software, hardware, and firmware. Develop system security policy and ensure compliance. Administer the user identification and authentication mechanisms of the Information System. Basic Qualifications Bachelor’s degree in a related field and at least 12 years of relevant experience. Additional experience may be substituted for a degree. TS/SCI with polygraph security clearance. Must have at least 10 years of experience as ISSO working independently, and/or on teams maintaining secure information system operations in isolated, connected and standalone environments. Must have at least 5 years of experience using tools to support IAVA management. Must have at least 5 years of experience using tools to support the preparation, maintenance, and management of SSPs and other security related documentation. Demonstrated knowledge of and experience with several of the following: current security tools; hardware/software security implementation; communication protocols; encryption techniques/tools. In-depth experience completing security evaluations of software systems or architectures to ensure they meet security requirements. In-depth experience proposing, coordinating, implementing, and enforcing information systems security policies, standards, and methodologies, preferably on a large software or IT program. Demonstrated experience performing day-to-day security operations of large, complicated information and information processing systems. Must be committed to developing and adhering to best practices. Must possess a high level of self-initiative and must be a solutions-oriented team player. Must have excellent interpersonal skills. Preferred Qualifications Extensive experience as an Information Systems Security Officer on large software development and integration programs. DoD 8570 compliance with IAT Level II or higher. DoD 8570 compliance with IAM Level II or higher. At Leidos, the opportunities are boundless. We challenge our staff with interesting assignments that allow them to thrive professionally and personally. For us, helping you grow your career is good business. We look forward to learning more about you – apply today. careers.leidos.com/CONMD

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CONMD

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares. Original Posting: July 20, 2026 For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above. Pay Range: Pay Range $131,300.00 - $237,350.00 The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.