Information Systems Security Officer (ISSO)

CesiumAstro•Austin, TX

About The Position

CesiumAstro is a developer of communication systems for satellites, UAVs, launch vehicles, and other space and airborne platforms. We are seeking an Information Systems Security Officer (ISSO) to assist with the development, implementation, and maintenance of our information security strategy. The ISSO is responsible for supporting the execution, maintenance, and continuous monitoring of information system security controls for classified and unclassified systems within an aerospace and defense environment. This role supports compliance with DoD cybersecurity requirements including NIST SP 800-53, NIST SP 800-171, RMF, and CMMC Level 2. The ISSO works under the direction of the ISSM and serves as a contributing team member, providing hands-on system security support, assisting with authorization and accreditation activities, and supporting ongoing compliance monitoring.

Requirements

Bachelor’s degree in Information Security, Computer Science, Engineering, or a related field, or equivalent practical experience.
Minimum of 2 years of experience in information system security, cybersecurity compliance, or ISSO-related roles within aerospace, defense, or government environments.
Experience supporting CMMC Level 2 compliance.
Experience supporting classified and unclassified information systems in a DoD or aerospace and defense environment.
Understanding of system authorization, continuous monitoring, and risk management processes.
Understanding of cybersecurity compliance and risk management principles.
Familiarity with SCIF operations and classified system security requirements.
Exposure to vulnerability scanning and assessment tools, security monitoring and logging tools, and GRC and compliance tools (e.g., eMASS or equivalent).
Working knowledge of NIST SP 800-171, NIST SP 800-53 and RMF concepts.
Experience with Microsoft Office Suite (Word, Excel, PowerPoint, Outlook).
Strong analytical, documentation, and communication skills.
Ability to operate independently while collaborating effectively with cross-functional teams.
Must be eligible to obtain and maintain a security clearance.

Nice To Haves

Experience supporting NIST SP 800-171 or CMMC Level 2 compliance is preferred.
Active U.S. DoD Secret clearance and DoD 8140 certification are not required but considered a plus.

Responsibilities

Assist with implementation and maintenance of security controls in accordance with NIST SP 800-53, NIST SP 800-171, RMF, and CMMC requirements.
Support system authorization activities including SSPs, POA&Ms, and security documentation.
Perform vulnerability tracking and support remediation efforts.
Support internal and external audits, assessments, and customer reviews.
Provide support for classified systems and SCIF environments under ISSM guidance.
Ensure adherence to classified system handling, marking, and access control requirements.
Assist with SCIF sustainment and compliance activities.
Assist in identifying, assessing, and documenting cybersecurity risks.
Support cybersecurity incident response, reporting, and remediation activities.
Participate in configuration change reviews to assess security impact.
Partner with IT, engineering, and program teams to support secure system operations.
Provide guidance to users on cybersecurity policies and procedures.
Support onboarding of systems and technologies into compliant environments.
Maintain accurate system security documentation.
Track compliance metrics and support audit readiness.
Contribute to continuous improvement of cybersecurity processes.