# Senior Penetration Tester at CoStar Group

- Company: CoStar Group
- Company website: https://www.costargroup.com
- Type: Startups
- Level: Senior
- Location: US-VA Arlington
- Work setup: On-site
- Posted: 2026-10-29
- Apply by: 2026-12-13
- Apply: https://costar.wd1.myworkdayjobs.com/en-US/CoStarCareers/job/US-VA-Arlington/Senior-Penetration-Tester_R38903?utm_source=1752vc&utm_medium=careers
- Page: https://www.1752.vc/careers/jobs/costar-group-senior-penetration-tester/

## About the role

Evolve our security pentesting capabilities to test our internal and external facing processes, infrastructure, and applications. This position will be tasked with developing test plans to validate identified vulnerabilities and demonstrate the exploitation of the vulnerabilities. The ability to explain the exploit to senior level management is key to success in this role. Stay current with trends, techniques, and tools used by adversaries. Found on 1752vc Careers, the job board for startup and VC roles.

## What they're looking for

- Lead penetration tests on web applications and underlying infrastructure for vulnerabilities using both manual and automated techniques
- Develop test plans that validate identified vulnerabilities and demonstrate exploitability to engineering teams, security peers, and senior leadership
- Collaborate with detection engineering and incident response on purple team exercises, validating that preventative and detective controls behave as expected against realistic adversary techniques
- Grow the team's pentesting capabilities in infrastructure and cloud-native domains, including CI/CD pipelines, Active Directory, AWS, and Kubernetes
- Recommend remediations that address root causes, including code changes, architectural improvements, and control adjustments
- Stay current with attacker tradecraft. Share knowledge with the broader security team and mentor engineers on offensive techniques and how to think like an attacker


Source: 1752vc Careers, https://www.1752.vc/careers/jobs/costar-group-senior-penetration-tester/