SlipstreamJobs tracks this role from the company's public career site. Apply directly on the employer's site.
Apex manufactures satellite buses at scale for the commercial aerospace industry, combining software, vertical integration, and hardware design to enable earth observation, communications, and other space-based applications.
You will serve as the Information Systems Security Officer (ISSO), acting as the security point of contact for operations and keeping teams informed on cyber posture. You will work closely with system owners, IT, engineering, the SOC, and the Cybersecurity Lead to ensure security requirements are implemented and supported by evidence that withstands customer and third-party review.
Key responsibilities include:
- Serve as the security point of contact for operations and maintain awareness of current cyber posture across teams
- Work with the Cybersecurity team to assess requirements, risk findings, and contract-driven due dates
- Maintain the System Security Plan (SSP), system inventory, policies, procedures, and supporting evidence for the CUI environment
- Track NIST SP 800-171 and CMMC Level 2 implementation at the artifact level
- Support Authorization to Operate (ATO) and Risk Management Framework (RMF) activities, including creating and updating security documentation and writing Plans of Action and Milestones (POA&Ms) with target completion dates
- Validate evidence from the cybersecurity suite including CrowdStrike, Palo Alto, Tenable, and Jira
- Lead vulnerability and configuration remediation with system owners, ensuring clear ownership, expectations, and target dates
- Lead security reviews on privileged accounts, terminated users, vulnerability results, and other security requests from the program
The primary focus is NIST SP 800-171 and CMMC Level 2 compliance. You will also support ATO activities, SOC 2 Type II, ISO-aligned compliance work, and other customer security requirements as Apex scales.
Apex is a fast-growing, well-funded startup ($500M+ raised) with a world-class office in Playa Vista offering in-person collaboration, catered lunch, comprehensive benefits including 100% company-paid healthcare, equity, 15+ days PTO, and a vibrant community culture.
REQUIREMENTS:
- Active TS/SCI clearance (required)
- US Citizenship (required)
- 3+ years of experience as an ISSO, security compliance analyst, security engineer, system administrator with security responsibilities, or similar role
- Strong working knowledge of NIST SP 800-171, CMMC Level 2, POA&M management, control evidence, and assessment preparation
- Experience maintaining an SSP or equivalent system security documentation and supporting formal security reviews
- Ability to understand and validate evidence from identity, cloud, endpoint, network, vulnerability, and logging platforms
- Strong follow-through across multiple teams and ability to write security documentation that clearly reflects actual implementation
PREFERRED QUALIFICATIONS:
- Experience with ATO, RMF, NIST SP 800-53, SOC 2 Type II, ISO 27001, DFARS 252.204-7012, SPRS, STIGs, or classified system security
- Experience with Microsoft GCC High, CrowdStrike, Palo Alto, Tenable, AWS GovCloud, Entra ID, or similar enterprise security platforms
- Security+, CGRC, CISSP, or comparable security certification
- Experience supporting aerospace, defense, national security, ATO, RMF, or other regulated technical environments
