Senior Penetration Tester – Zero Trust Setup Upgrade

Keystone Digital

Contract · Remote · Flexible hours

About the role

Keystone Digital is expanding its multi‑tenant security layer for a flagship B2B SaaS platform. As a Senior Penetration Tester you will drive the security validation of new tenant isolation features, ensuring the product meets strict compliance standards before release.

Key responsibilities

• Perform comprehensive black‑box and white‑box penetration tests on the upcoming tenant isolation module, named "VaultGuard".
• Develop and execute automated attack scripts using Python and Burp Suite to simulate cross‑tenant data leakage scenarios.
• Collaborate with the DevSecOps team to integrate findings into CI/CD pipelines, providing remediation guidance for identified vulnerabilities.
• Produce detailed technical reports with proof‑of‑concept exploits, risk ratings, and remediation steps within two‑week sprint cycles.
• Present live demo of critical exploits to product owners and engineering leads, driving immediate fix prioritization.
• Maintain a secure testing environment on Linux containers, ensuring no impact on production tenants.

Must-have skills

• Advanced expertise in network and application penetration testing (OWASP Top 10, API security).
• Proficiency with Kali Linux, Burp Suite, Metasploit, and custom Python exploit scripts.
• Experience testing multi‑tenant SaaS architectures and cloud environments.
• Strong understanding of vulnerability remediation and secure coding practices.
• Excellent documentation and communication skills for technical and non‑technical audiences.

Nice to have

• Familiarity with container security tools such as Trivy or Aqua.
• Certifications like OSCP or OSCE.