Senior Cloud Platform Security Engineer

Senior Cloud Platform Security Engineer Overview CoStar Group (NASDAQ: CSGP) is a leading global provider of commercial and residential real estate information, analytics, and online marketplaces. This position is located in Arlington, VA or Richmond, VA and offers a schedule of Monday through Thursday in office and Friday work from home. Responsibilities Cloud Security and Guardrails: Enforce security posture across AWS, GCP, and Azure through preventative controls (SCPs, organization policies, IAM guardrails) and detective controls (Wiz, native cloud security services). Build detection patterns and escalation paths in partnership with incident response. Drive validation methodology and operational rigor across acquisitions and new environments. Kubernetes Platform Security: Lead workload protection strategy across EKS clusters, including runtime monitoring, admission control, network policy, and secrets management. Drive sensor coverage validation, incident response readiness, and security guardrails that scale across the portfolio. AI and Agentic System Security: Partner with product engineering on securing AI‑powered features, MCP server implementations, and agentic workflows across the portfolio. Lead threat modeling for new AI surfaces, build guardrails and detection patterns for prompt injection and unauthorized tool use, and shape security standards as the company expands AI capabilities into customer‑facing products. Security Automation: Integrate automated scanning tools into CI/CD pipelines, implement IaC solutions, and drive automated remediation processes. Mentorship & Collaboration: Work closely with product dev teams to provide feedback on secure coding practices, proactively guide them on risk remediation, and provide guidance to other security team members. Basic Qualifications Bachelor’s Degree required from an accredited university (preferably in Computer Science, Cybersecurity or a related field). 6+ years of hands‑on security engineering experience with depth in at least one of the following domains: securing cloud‑native environments (AWS preferred), Kubernetes platform hardening or monitoring, CI/CD pipelines, containerized application deployments, and IaC, and software supply chain security. Track record of taking security initiatives from scoping through production rollout and operational ownership. Ability to author scripts or IaC from scratch in Python, PowerShell, Ansible, CloudFormation, Terraform, or similar. Experience securing AI‑powered applications, including threat modeling for LLM‑based features, MCP server implementations, or agentic systems. Experience working in a software development environment with a mature CI/CD. Passion for solving complex challenges and innovating. Demonstrated commitment to prior employers. Preferred Qualifications A self‑starter who can advance the platform security program and follow through ideas to completion. Experience with tools and services such as AWS GuardDuty, Security Hub, EKS, OPA/Gatekeeper, Falco, Wiz, Datadog, Prisma Cloud, Orca, Upwind, Snyk, or similar. Familiarity with software supply chain security, including SBOM generation, dependency vulnerability management, build provenance, and artifact signing. Knowledge of infrastructure operations across databases, network, and system administration. Effective use of AI tools as a force multiplier for engineering work. Ability to communicate with different levels of leadership conveying risk and driving urgency for risk remediation. Familiarity with zero trust principles and cloud‑native access controls. Ability to mentor and train team members to prioritize security efforts effectively. Hands‑on experience implementing security tools into CI/CD pipelines. Experience testing serverless cloud deployments. Benefits Comprehensive healthcare coverage: medical, vision, dental, prescription drug. Life, legal, and supplementary insurance. Virtual and in‑person mental health counseling services. Commuter and parking benefits. 401(K) retirement plan with matching contributions. Employee stock purchase plan. Paid time off. Tuition reimbursement. On‑site fitness center and/or reimbursed fitness center membership costs (location dependent), with yoga studio, Peloton, personal training, group exercise classes. Access to CoStar Group’s Employee Resource Groups. Complimentary gourmet coffee, tea, hot chocolate, fresh fruit, and other healthy snacks. We welcome all qualified candidates who are currently eligible to work full‑time in the United States to apply. Please note CoStar Group is not able to provide visa sponsorship for this position. CoStar Group is an Equal Employment Opportunity Employer; we maintain a drug‑free workplace and perform pre‑employment substance abuse testing. #J-18808-Ljbffr Costar Inc