Offensive Security Engineer (Mobile)

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

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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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