Senior Security Engineer - Offensive Security

Stockholm, Sweden /
Engineering /
/ Hybrid
On our path to becoming the world’s favorite way to shop, we’re assembling an unparalleled global talent network, accelerating individual careers, and disrupting entire industries. We are on a mission to liberate humanity from all the meaningless time spent managing their purchases and finances, so they can do more of what they love. We’re in search of global talent eager to embrace our atmosphere and defy their own expectations.

Engineering at Klarna is an inspired, customer focused community, dedicated to crafting solutions that redefine our industry. Working in small, highly collaborative Agile teams, you and your team will have a clear mission and ownership of an important outcome that supports Klarna and our customers. At Klarna we optimise for quality, flow, fast feedback, focussing on end-to-end ownership, continuous improvement, testing, monitoring and experimentation. We aim for teams that are inclusive, helpful, and have a strong sense of ownership for the things they build.

Our engineers make some of the most significant decisions for the company, and we are looking for bold, open, and curious developers. As a Klarnaut, you’ll be inspired to contribute to the growth of Europe’s most highly valued fintech, and your work will reach millions of users.

You are a hacker. You love breaking stuff. You are also an engineer. We want to give you the freedom to work across the offensive space where it provides the most value.

What you'll get to do

    • Break all the things.
    • Conduct white-box and black-box penetration testing against internal and public-facing applications and assets.
    • Manage, triage, and investigate Bug Bounty submissions and external pentest findings.
    • Perform variant analysis on issues discovered through all channels.
    • Research and perform security analyses on Klarna’s 3rd-party solutions.
    • Develop tooling to support reconnaissance, automation, and metrics collection.
    • Provide expert guidance to developers, other product security teams, and the SOC in investigating issues.
    • Spread awareness of offensive security practices via demos, workshops and training.
    • Assess the security of our tech stack through whatever means are best suited.
    • Define what we focus on to provide the most value.
    • Help further mature Klarna’s security program.

To succeed in this role, we think you should have/be

    • Strong experience with penetration testing and other technical security assessments.
    • Experience identifying security issues in code, particularly within Java and Node.js
    • Experience with cloud environments, particularly AWS and modern micro-service design principles.
    • Comfortable communicating findings clearly and effectively, with concrete remediation recommendations beyond simple issue reporting.
    • Comfortable scripting and contributing to larger projects in Python.
    • Able to take initiative and be comfortable taking on projects that contribute to the larger security culture and posture at Klarna.
    • Industry recognised certifications, e.g. OSCP, OSWE, CREST, GIAC, AWS, et. al.
    • CTF Participation and active contributions to the cybersecurity community.

    • We also believe in contributing back to the open-source community. You can find some of our work here

What we offer:

Diversity & Community
With our diversity of skills, perspectives and backgrounds, we can create, innovate, and disrupt like no other. Diversity is part of who we are, and essential to our success.

Ownership & Impact
Here, every voice matters. We’re organized into hundreds of small teams, each run like a start-up, focused on their own problem-space.

Trust & Collaboration
Successes and failures are won together at Klarna in a melting pot of teams. Win, lose, and learn, we’re on this path together.

If you love what you do, you should love where you do it. We appreciate that everyone’s different and has their own preferences of where and how to work. We genuinely believe in the power of regular face-to-face interactions in building close connections with our teams, but we also strongly believe people can work effectively remotely. This means that combining both is the key to success. 

At Klarna, You can choose between working from the office, remotely within your employment country, or even outside of it for up to 20 working days per year. Flex it up!  

Challenges & Rewards
We take a very Swedish approach to benefits. Support for parents, health and wellness perks—we’ve got you covered.

About Klarna
Since 2005 Klarna has been on a mission to revolutionize the retail banking industry. With over 150 million global active users and 2 million transactions per day, Klarna is meeting the changing demands of consumers by saving them time and money while helping them be informed and in control. Over 450,000 global retail partners, including H&M, Saks, Sephora, Macys, IKEA, Expedia Group, and Nike have integrated Klarna's innovative technology to deliver a seamless shopping experience online and in-store. Klarna has over 6,000 employees and is active in 45 markets. For more information, visit

It is our commitment that every qualified person will be evaluated according to skills regardless of age, gender, identity, ethnicity, sexual orientation, disability status or religion. Please refrain from including your picture and age with the application.