Senior Application Security Engineer
CoStar GroupSydney
Posted February 25, 2026
Full Time
About the Company
CoStar Group (NASDAQ: CSGP) is a global leader in commercial real estate information, analytics, online marketplaces and 3D digital twin technology. Founded in 1986, CoStar Group is dedicated to digitizing the world’s real estate, empowering all people to discover properties, insights, and connections that improve their businesses and lives. CoStar Group’s major brands include CoStar, a leading global provider of commercial real estate data, analytics, and news; LoopNet, the most trafficked commercial real estate marketplace; Apartments.com, the leading platform for apartment rentals; and Homes.com, the fastest-growing residential real estate marketplace. CoStar Group’s industry-leading brands also include Matterport, a leading spatial data company whose platform turns buildings into data to make every space more valuable and accessible, STR, a global leader in hospitality data and benchmarking, Ten-X, an online platform for commercial real estate auctions and negotiated bids and OnTheMarket, a leading residential property portal in the United Kingdom. CoStar Group’s websites attracted over 134 million average monthly unique visitors in the fourth quarter of 2024, serving clients around the world. Headquartered in Arlington, Virginia, CoStar Group is committed to transforming the real estate industry through innovative technology and comprehensive market intelligence. From time to time, we plan to utilize our corporate website as a channel of distribution for material company information. For more information, visit CoStarGroup.com.
Job Description
We are seeking a Senior Application Security Engineer to play a pivotal role in enhancing our Application Security (AppSec) practices, ensuring that security is embedded throughout the software development lifecycle. As a seasoned expert, you will report to the Group Engineering Manager - Product Security and work with development teams to guide and advise them on best practices.
Requirements
- Proactively embedding security into the software development lifecycle by conducting implementation reviews of solution designs and leading threat modelling sessions.
- Leading efforts to integrate security into DevOps processes, promoting a culture of security awareness and ownership.
- Performing hands-on security code reviews and acting as a key security advisor to development teams, providing guidance on addressing vulnerabilities and best practices.
- Managing and operating our security tools, including those that are integrated into the CI/CD pipeline.
- Partnering with the Governance, Risk & Compliance (GRC) and Security Operations teams to ensure adherence to relevant regulations and industry standards and collaborating and supporting the investigation and response to security incidents.
