Offensive Security Engineer (Mobile)

Offensive Security (Mobile) | £65-75k DOE | Hybrid Working (UK)

We're working with an innovative UK technology company operating at the forefront of digital identity and biometric security. As their security function continues to grow, they're looking to appoint an experienced Offensive Security Engineer with a strong focus on mobile application security.

The Opportunity:

You'll take ownership of sophisticated red team and mobile security assessments across iOS and Android environments, simulating real-world attack scenarios to identify vulnerabilities before they can be exploited.

The role combines hands-on offensive testing, exploit development, research into emerging threats, and close collaboration with engineering teams to ensure vulnerabilities are remediated effectively.

This position would suit someone who enjoys reverse engineering, breaking mobile protections, and staying ahead of evolving threats in areas such as biometrics, authentication, and device compromise.

Key Responsibilities:

• Conduct advanced mobile application penetration testing across iOS and Android
• Perform reverse engineering, runtime manipulation, and instrumentation attacks
• Simulate realistic adversarial scenarios including:
  • Rooted and jailbroken devices
  • Emulator and Frida-based attacks
  • Certificate pinning bypass
  • Session manipulation and API abuse
  • Biometric spoofing and presentation attacks
• Identify weaknesses in authentication, cryptographic controls, and mobile architectures
• Develop proof-of-concept exploits and custom tooling
• Produce high-quality reports with practical remediation guidance
• Work closely with software engineers and product teams to validate fixes
• Research emerging mobile attack techniques and adversarial methods
• Support improvements to security monitoring and detection capabilities
• Mentor development teams on secure mobile development practices

About You:

You will have strong experience in offensive security, penetration testing, or mobile security research, with a genuine passion for understanding how complex systems can be attacked and improved.

Essential Experience:

• 4+ years in Red Teaming, Penetration Testing, or Mobile Security
• Deep expertise in Android and/or iOS application security
• Strong experience with tools such as:
  • Frida
  • Ghidra
  • Hopper
  • IDA Pro
  • Burp Suite
• Experience analysing APK and IPA binaries
• Ability to bypass certificate pinning, anti-debugging, and anti-tamper controls
• Strong understanding of:
  • Android and iOS security models
  • Secure storage (Keychain / Keystore)
  • Cryptographic implementations
  • OAuth and authentication protocols
• Scripting and automation skills to build custom testing tools
• Excellent communication skills and the ability to explain findings clearly

Desirable:

• Experience with biometric systems and identity verification technologies
• Security research background
• Contributions to open-source tooling or vulnerability research
• Exposure to threat modelling and secure architecture reviews

If this sounds like you, apply now or reach out directly.

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