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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Application Security Penetration Engineer - **Company:** Citi - **Location:** Tampa, FL, United States - **Experience:** Starter - **Salary:** $96,400.0 - $144,600.0 - **Contract:** Permanent contract - **Skills:** ASP.NET, Java (Programming Language), .NET Framework, Application Programming Interfaces (APIs), Artificial Intelligence, Amazon Web Services, Applications Architecture, Application Frameworks, Business Logic, Software System Penetration Testing, Automation of Tests, Microsoft Azure, Burp Suite, C Sharp (Programming Language), C++ (Programming Language), Cloud Computing, Static Program Analysis, CompTIA Security+, Cyber Security, Databases, Middleware, Fuzz Testing, Web Servers, Spring Framework, Apache Struts, Python (Programming Language), Nmap, Node.Js, Open Web Application Security, Ruby, Software Safety, Software Engineering, SonarQube, Web Applications, Webinspect, Google Cloud, ReactJS, Large Language Models, Multi-Agent Systems, Software Security, Generative AI, GWAPT, Containerization, AngularJS, Bug Reporting, Information Technology, Synopsys Black Duck, Nessus, Checkmarx, Appscan, Serverless Computing, Vulnerability Analysis, Microservices - **Published:** October 15, 2026 - **Apply:** https://www.dice.com/job-detail/24d4f183-5d26-4233-a84c-36053c8c0bd4 ## About the Role * Minimum of 1-3 years of hands-on experience in penetration testing, application security assessment, or software development ideally in an enterprise environment. * Hands-on experience with dynamic/proxy/network testing tools such as Burp Suite Proxy, AppScan, WebInspect, Nessus, NMAP, or OWASP ZAP. * Hands-on experience with static analysis and software composition tools such as Checkmarx, BlackDuck, SonarQube, or Snyk. * Exposure to AI security/adversarial testing tools such as Garak, PyRIT, Counterfit, or the Adversarial Robustness Toolbox (ART) is advantageous. * Strong foundation in enterprise programming and scripting languages, including Python, Java, .NET/C#, C/C++, Ruby, and/or NodeJS. * Familiarity with common web and application framework stacks, such as Spring, AngularJS, React, Struts, ASP.NET Core, or AI orchestration libraries. * Deep knowledge of application architectures and enterprise infrastructure, including databases, middleware, web servers, and cloud computing (Google Cloud Platform, AWS, Azure) supporting microservices and containerized workloads. * Deep knowledge of common industry security standards, including OWASP Top 10 and CWE/SANS Top 25. * Working familiarity with emerging AI security standards, including OWASP Top 10 for LLMs, MITRE ATLAS, and NIST AI RMF. Education * Bachelor\'s degree in Computer Science, Cybersecurity, Information Technology, or a related discipline. Equivalent professional or hands-on experience may be considered in lieu of a degree. * Must have or be willing to obtain industry-accredited security certifications such as OSCP, OSWE, GWAPT, GWEB, GPEN, GXPN, GMOB, CISSP, CEH, CompTIA Security+, or CySA+. ## Description Citi is seeking an Application Security Penetration Tester to join its Offensive Security team, conducting deep-dive vulnerability assessments across web applications, mobile, thick clients, APIs, microservices, and emerging Generative AI/LLM implementations. This role is well-suited for either an experienced penetration tester looking to deepen their offensive security career or a software developer/engineer seeking to transition into cybersecurity. The analyst will manually identify, research, validate, and safely exploit known and zero-day vulnerabilities, then translate technical findings into clear risk guidance for developers, architects, and ML engineers. A key focus of the role is researching and applying LLM-based security testing techniques to uncover complex, non-obvious vulnerabilities that evade traditional automated and manual testing. The team supports pentesting of the firm\'s most critical applications while actively researching AI/LLM-driven automation to enhance pentest effectiveness. Responsibilities * Conduct manual vulnerability assessments and penetration testing across applications and/or infrastructure. * Identify and validate potential security vulnerabilities across Citi applications, APIs, cloud-native services, and AI/ML architectures. * Engineer functional proof-of-concept code and exploit scenarios to demonstrate the exploitability and tangible impact of identified security weaknesses. * Research and use LLM-based security testing harnesses to uncover deeply embedded, non-obvious vulnerabilities. * Identify multi-step business logic abuse chains, cryptographic flaws, and complex privilege escalation paths that evade manual and traditional automated testing. * Accurately document discovered vulnerabilities, reproduction steps, attack chains, and risk ratings in standardized assessment reports. * Report and articulate vulnerability assessment results to both technical and non-technical audiences. * Clearly articulate vulnerabilities to application developers, system architects, and ML engineers. Ensure they understand the root causes and true business risks. * Drive remediation by outlining a defense-in-depth approach to business stakeholders. * Propose actionable mitigating controls, code-level remediation solutions, and AI safety guardrails to developers to fully close security gaps. * Keep abreast of emerging offensive security techniques. Participate in threat modeling exercises and adversarial testing across both traditional and AI-driven technology stacks. * Support pentesting engagements for the firm\'s critical, top-tier applications. * Research new ways to automate pentest activities, including the use of AI/LLM tooling, to identify vulnerabilities more effectively.