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Sr. Penetration Tester (Adversarial Operations)

Bishop Fox

Bishop Fox

Spain · United Kingdom
Posted on Thursday, February 8, 2024

Bishop Fox is the leading authority in offensive security, providing solutions ranging from continuous penetration testing, red teaming, and attack surface management to product, cloud, and application security assessments. We’ve worked with more than a quarter of the Fortune 100, half of the Fortune 10, eight of the top 10 global technology companies, and all of the top global media companies. Our Cosmos platform, service innovation, and culture of excellence continue to gather accolades from industry award programs including Fast Company, Inc., SC Media, and others. For more than 16 years, we've been contributing and giving back to the security community. We’ve published more than 16 open source tools and 50 security advisories in the last five years alone. Learn more at or follow us on social media.

We’re looking for talented, experienced professional hackers to help us secure some of the world’s most complex software and sophisticated technologies. You’ll be working alongside our US and other internationally-based teams supporting clients across multiple industries.

Who You Are and What You’ll Do

Cosmos proactively defends dynamic attack surfaces by combining advanced technology, automation and expert-driven testing by a team of talented offensive security analysts, operators, and developers from a variety of diverse backgrounds. We tackle the challenge of discovering, analyzing, and testing online assets at scale. Together we are building the latest in automation to empower offensive security practitioners to efficiently deliver findings to some of the world's largest companies.

As a Bishop Fox Cosmos operator, you’ll be empowered by technology to find and exploit vulnerabilities across an ever-increasing external attack surface. You’ll use your hacker mindset to compromise networks and applications while constantly thinking about how to scale your efforts and broaden your reach. You’ll also develop tools and techniques to increase attack surface discovery, identify new attacks of opportunity, and perform in-depth network and web application testing on high-value targets.

Your Education and Experience

You just have to be good at and, most importantly, love what you do. Here’s a list of qualities we’re looking for, but don’t think that you need them all:

  • Web application penetration testing
  • Network penetration testing
  • Open-source intelligence gathering (OSINT)
  • Scripting/programming skills (e.g., Python, Golang, Node.js, Bash, etc.)
  • Red teaming
  • Strong communication skills (i.e., written and verbal)
  • Active GitHub account
  • Extensive experience with and contributions to bug bounty programs
  • Understanding of security fundamentals and common vulnerabilities (e.g., the OWASP Top Ten)
  • 2–5 years of application security experience
  • Additional experience in IT, security engineering, system and network security, authentication and security protocols, or applied cryptography
  • Network and web-related protocol knowledge (e.g., TCP/IP, UDP, IPSEC, HTTP, HTTPS, routing protocols)

Bishop Fox has always allowed its employees to work remotely, and this role could work anywhere in United Kingdom and Spain. Our comprehensive benefits program is tailored to meet your needs at an affordable price. We embrace diversity and an inclusive culture. We value our employees and who they are, which fosters a powerful and collective talent base to successfully serve our clients and the security community with unparalleled expertise.

All qualified applicants will receive consideration for employment without regard to age, race, color, religion, sex, sexual orientation, gender identity, national origin, or veteran status

Interested? Apply today!