2 months ago
Stockholm, SwedenSenior
Responsibilities
- Run white-box and black-box penetration tests against internal systems and public-facing applications.
- Manage, triage, and investigate bug bounty submissions and external penetration-testing findings.
- Perform variant analysis to identify related vulnerabilities across the codebase and infrastructure.
- Research and assess the security of third-party solutions and integrations.
- Build tooling for reconnaissance, automation, and metrics collection.
- Guide developers, product security teams, and SOC investigations through hands-on security expertise.
- Run demonstrations, workshops, and training on offensive security practices.
- Assess Klarna’s technology stack and help mature the overall security program.
Requirements
- At least 5 years of experience running penetration tests and technical security assessments against production systems.
- Ability to read code and identify vulnerabilities, particularly in Java and Node.js.
- Experience operating in AWS and reviewing microservice architectures for security gaps.
- Ability to document findings clearly and provide concrete remediation steps.
- Ability to script security tooling in Python.
- Ability to independently advance offensive security initiatives.
- Industry certifications such as OSCP, OSWE, CREST, GIAC, or an AWS security certification are advantageous.
- Active participation in CTFs or the broader security research community is advantageous.
- Public security research such as CVEs, conference talks, or published tooling is advantageous.
- CV in English is requested.
Benefits
- The position is based in Klarna’s Stockholm office.
- Most teams currently meet in person 2–3 days per week, with arrangements varying by team and subject to change.
- Non-obvious backgrounds and diverse skills, perspectives, and backgrounds are welcomed.
About Klarna
Klarna is a privately held fintech that provides buy now, pay later financing, checkout, and a consumer shopping app for e-commerce and retail. It monetizes through merchant fees, interchange, and interest and fees on financing, while offering marketing and customer acquisition tools to merchants. Founded in 2005 and headquartered in Stockholm, it operates across Europe and North America.