← Back to results

Mission Security Engineer

Join Apex Space as a Mission Security Engineer to contribute to the authorization posture of space vehicles and classified cloud environments.

Location
Los Angeles
Compensation
Not disclosed
Level
Not specified
Type
full time

Posted by employer 3 days ago

First seen on Joblaze 1 month ago

Last verified on the company career page 1 hour ago

Apply at Apex Space → Save job Scanned from apexspace.com

Skills & Technologies

What you'll build

  • Build and sustain authorization packages
  • Own the POA&M
  • Define the authorization boundary for mission systems
  • Implement controls as code
  • Manage security incident reporting

Must have

  • U.S. Citizenship
  • Active Top Secret clearance
  • Experience with technical tooling

Nice to have

  • Experience with OSCAL
  • Skilled in Python, Go
  • Experience with continuous authorization

Practical constraints

  • Must possess the ability to access export-controlled data

AI in the day-to-day

Use AI-assisted drafting and crosswalk tooling for control narratives and monitoring summaries.

Requirements

Experience
1–10 years
Education
Bachelor's degree

Not disclosed in this posting: compensation, seniority, work arrangement, visa sponsorship.

Benefits

401k Match Equity/Stock Options Health Insurance Parental Leave

Joblaze summary

The Mission Security Engineer at Apex Space is responsible for managing the authorization posture of both a space vehicle and a classified cloud mission operations environment, focusing on cyber engineering and continuous monitoring. Key skills include experience with RMF documentation, cloud environments, and embedded systems, with a strong emphasis on security compliance. This role is suitable for candidates ranging from recent graduates to seasoned professionals with backgrounds in systems engineering or cybersecurity, particularly those familiar with national security protocols.

Joblaze insights

  • Listed about a month ago — first seen on Joblaze September 19, 2026. Last confirmed on Apex Space's careers page November 6, 2026.
  • Python appears in 38.6% of 898 comparable security roles in United States; RMF appears in 0.2% of 898 comparable security roles in United States.

Quick facts

How much experience is required?
1–10 years of relevant experience for this Mission Security Engineer role.
What's the tech stack?
Joblaze extracted these technologies from the posting: Cloud, Go, OSCAL, Python, RMF, eMASS.
Is this full-time or contract?
Full-time for this Mission Security Engineer role at Apex Space.

From the original posting

About the Role

In this position, you will own or contribute to the authorization posture of two systems: a space vehicle and a classified cloud mission operations environment. You will contribute to cyber engineering and produce RMF authorization documentation, build and sustain authorization packages, own the plan of action and milestones day to day, and run continuous monitoring. This is mission systems work throughout, not traditional enterprise IT security.

We are open to candidates from ISSE, SSE, ISSM, or ISSO backgrounds, and are hiring across levels: from new and recent graduates through senior engineering, officer, and manager experience.

Responsibilities:
May include any or all of the following:

Authorization Ownership

  • Build and sustain authorization packages for both boundaries: system description, boundary definition, categorization, control selection and tailoring rationale, implementation statements, assessment coordination, and the residual risk picture carried to the AO.

  • Get assessors engaged early on our evidence-generation approach so generated artifacts are trusted before a package depends on them.

  • Own the POA&M.

  • Maintain the authorization system of record (eMASS or equivalent).

Space Vehicle Segment

  • Own the authorization boundary determination for the flight segment and the rationale that survives assessor scrutiny.

  • Categorize under CNSSI 1253 and defend overlay selection, treating the Space Platform Overlay as the starting place it is rather than a finished answer — pushing back where our onboard security capability exceeds what the published tailoring assumes.

  • Tailor the control baseline with per-control rationale, using Aerospace's Space Segment Cybersecurity Profile (TOR-2023-02161 Rev A) and SPARTA-linked tailoring, including arguing controls back in where our onboard capability exceeds what those baselines assumed.

  • Define the type-authorization for the bus and design how each vehicle off the line generates its own conformance evidence so fleet growth does not mean linear growth in assessment labor.

  • Derive verifiable security requirements from threat using SPARTA TTPs as the traceability key, owned by the software and mission integration engineers who will build and test against them.

  • Translate verification and production artifacts into assessment evidence and tell engineering early when what they produce will not satisfy an assessor.

  • Own the continuous monitoring story for a fielded fleet: security audit downlinked across contact windows, configuration drift across vehicles, and on-orbit software update as a recurring authorization event.

Classified Cloud Mission Operations Environment

  • Define and document the authorization boundary for mission systems in classified cloud (AWS, Azure classified regions, or equivalent), including impact-level scoping and the seam with ground stations and the RF edge.

  • Own the control and evidence story for operator command authority: identity, role separation, least privilege, two-person integrity, non-repudiation, and complete audit of every command that reaches the vehicle.

  • Build and defend the control inheritance model and prove the customer-responsible set with live evidence rather than assertion, validating what the cloud service provider and the platform satisfy versus what remains customer responsibility for the mission-unique applications.

  • Implement controls as code, so infrastructure-as-code, policy-as-code, and pipeline configuration serve as the implementation and the evidence at once.

  • Make change control and continuous monitoring work at operations tempo, never putting a contact window at risk, positioned for the DoD transition toward the Cybersecurity Risk Management Construct (CSRMC) and continuous authorization.

  • Manage security incident reporting and coordination for the boundary.

Automation and Generation

  • Define what evidence you need and in what form.

  • Design the OSCAL-based evidence data model and the mapping layer that resolves a property assertion to control identifiers across 800-53, CNSSI 1253 baselines, overlays, and program-unique control sets.

  • Build the pipeline that renders SSP sections, assessment evidence, POA&M items, and continuous monitoring reports deterministically from pinned evidence snapshots.

  • Integrate with the authorization system of record (eMASS or equivalent) programmatically, so generated artifacts land where assessors actually look.

  • Use AI-assisted drafting and crosswalk tooling for control narratives, framework mappings, and monitoring summaries, with human review on anything an AO reads and full traceability from every statement to a source record.

  • Push toward controls whose satisfaction is demonstrated by system state rather than by narrative.

Required Qualifications

At Every Level

  • U.S. Citizenship (must possess the ability to access export-controlled data)

  • Active Top Secret clearance with SCI access and SAP eligibility strongly preferred

  • Experience with technical tooling: reading pipeline output, querying an API, interpreting scanner and configuration state

Entry Level (1–3+ Years)

  • Bachelor's, master's, or PhD in systems engineering, computer science, cybersecurity, aerospace, or a related field

  • Clear experience with hands-on building via coursework, internships, research code, personal projects, CTFs, a co-op, or an early role and/or some exposure to RMF, security compliance, cloud, or software engineering

  • Willingness to learn RMF from the ground up, with a demonstrated ability to pick up a complicated technical domain quickly and hold a lot of detail without losing the thread

Senior Level (5–10+ Years)

  • Strong experience in embedded/space systems or cloud infrastructure

  • Multiple systems taken to authorization in national security or DoD environments, with fluency in RMF as practiced: categorization under CNSSI 1253, overlay selection, tailoring rationale, assessment coordination, POA&M management, continuous monitoring, and reauthorization triggers

  • Ability to speak concretely about categorization, tailoring, assessment, and authorization, and to design, document, or test a report and determine whether it constitutes evidence that a control is satisfied

  • Direct experience with at least one accredited cloud environment and one non-traditional system such as embedded, weapons, platform IT, industrial, or space

Preferred Qualifications

  • Experience with OSCAL, eMASS APIs, Xacta, controls-as-code, or continuous-controls-monitoring implementation

  • Skilled in Python, Go, or equivalent, in CI/CD, infrastructure-as-code, and Git-based workflows

  • Experience with continuous authorization, ongoing authorization, or cATO

  • Experience building with AI-assisted development

  • Understanding of Mission Operations including satellite command and control, mission planning, flight dynamics, telemetry processing, or multi-mission ground segments

  • Embedded or safety-critical background in space, automotive, or industrial control

  • Experience with SPARTA, NIST IR 8270 or IR 8401, CCSDS security standards, Space Platform Overlay, NASA/Space Force system protection standards, or space-system threat modeling

  • Experience with classified cloud accreditation at IL5/IL6 or IC equivalents, or accreditation under JSIG or ICD 703

  • Qualified, or able to qualify, under DoDM 8140.03 for a systems security engineering, security architecture, or Information Systems Security Manager work role. CISSP, CISSP-ISSEP, CISM, and SecurityX map well.

#LI-RC1

What We Offer For Full-time Employees:

  • Shared upside: Receive equity in Apex, letting you benefit from the work you create

Standard company text repeated across Apex Space's postings is omitted here.

Similar positions

Apex Space
Cybersecurity Engineer
Apex Space · Los Angeles
Apex Space
Cybersecurity Lead Engineer
Apex Space · Los Angeles
Apex Space
Cybersecurity Lead (TS)
Apex Space · Los Angeles