Senior Mobile Security Engineer – Offensive Testing

Klarna; Bardi; In loco; EUR 70.000 - 110.000; Tempo pieno

Descrizione del lavoro

Klarna is seeking a Senior Mobile Security Engineer to lead offensive security testing for its iOS and Android apps. You will collaborate with engineering teams to turn findings into fixes and improve app hardening, driving real security improvements in a fast-moving fintech environment.

You will apply MASVS/MASTG guidelines and perform hands-on testing, reverse engineering, and production-ready remediation, with a focus on reducing risk across Klarna’s mobile ecosystem.

Competenze

• Hands-on offensive mobile security testing experience on iOS/Android.

Mansioni

• Run offensive security assessments (penetration tests, red-team exercises, vulnerability discovery) on Klarna’s mobile apps (iOS/Android).
• Reverse-engineer app binaries to uncover sandboxing, permissions, and core security weaknesses.
• Test against OWASP MASVS/MASTG and translate results into actionable fixes with engineering teams.
• Evaluate and stress-test app-hardening and RASP protections.
• Document findings in actionable formats and ensure fixes are implemented in production.
• Hands-on offensive mobile security experience against iOS/Android.
• Strong understanding of mobile internals: sandboxing, permissions, security architectures of iOS and Android.
• Familiarity with OWASP MASVS/MASTG as primary framework for security assessments.
• Experience with app-hardening and RASP; fintech/payments app security a plus.
• Published CVEs, talks, or track record in mobile security or bug bounty (bonus).
• Experience shipping production mobile code or similar.
• Familiarity with Play Integrity/App Attest and device-binding schemes (bonus).
• Strong written and verbal communication with engineers.
• Curiosity and meticulous attention to detail.
• OWASP MASVS/MASTG
• Frida
• Objection

Conoscenze

Offensive security testing

Penetration testing

Reverse engineering

Mobile security

Security research

Documentation

Strong communication

Bug bounty experience

Production code shipping

Play Integrity/App Attest knowledge

Strumenti

Frida

Objection

MobSF

jadx/apktool

Ghidra/Hopper

Burp Suite

mitmproxy

Descrizione del lavoro

Klarna is seeking a Senior Mobile Security Engineer to lead offensive security testing for its iOS and Android apps. You will collaborate with engineering teams to turn findings into fixes and improve app hardening, driving real security improvements in a fast-moving fintech environment.

You will apply MASVS/MASTG guidelines and perform hands-on testing, reverse engineering, and production-ready remediation, with a focus on reducing risk across Klarna’s mobile ecosystem.