Job Description
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 AndroidPerform reverse engineering, runtime manipulation, and instrumentation attacksSimulate realistic adversarial scenarios including: Rooted and jailbroken devicesEmulator and Frida-based attacksCertificate pinning bypassSession manipulation and API abuseBiometric spoofing and presentation attacksIdentify weaknesses in authentication, cryptographic controls, and mobile architecturesDevelop proof-of-concept exploits and custom toolingProduce high-quality reports with practical remediation guidanceWork closely with software engineers and product teams to validate fixesResearch emerging mobile attack techniques and adversarial methodsSupport improvements to security monitoring and detection capabilitiesMentor development teams on secure mobile development practicesAbout 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 SecurityDeep expertise in Android and/or iOS application securityStrong experience with tools such as: FridaGhidraHopperIDA ProBurp SuiteExperience analysing APK and IPA binariesAbility to bypass certificate pinning, anti-debugging, and anti-tamper controlsStrong understanding of: Android and iOS security modelsSecure storage (Keychain / Keystore)Cryptographic implementationsOAuth and authentication protocolsScripting and automation skills to build custom testing toolsExcellent communication skills and the ability to explain findings clearlyDesirable:Experience with biometric systems and identity verification technologiesSecurity research backgroundContributions to open-source tooling or vulnerability researchExposure to threat modelling and secure architecture reviewsIf this sounds like you, apply now or reach out directly.Oscar Associates (UK) Limited is acting as an Employment Agency in relation to this vacancy.To understand more about what we do with your data please review our privacy policy in the privacy section of the Oscar website.TPBN1_UKTJ