Penetration Tester, AI/LLM Focus — Hybrid

Deloitte France; Madrid; Hybrid; EUR 65,000 - 100,000; Full time

Benefits offered by this job

Hybrid work model

Wellbeing programs

Volunteer initiatives

Deloitte University in Paris

Job summary

Deloitte is seeking a Senior Penetration Tester to join the Global Cyber Services team in Madrid. You will execute testing across web apps, APIs, networks, mobile and AI/LLM-based systems, delivering clear findings and actionable recommendations.

Ideal candidates have 4+ years in pen testing, hands-on tooling experience (Kali, Burp, Nmap, Metasploit, sqlmap, AMASS) and familiarity with OWASP Top 10. Strong English skills are required; Spanish fluency is a plus.

Qualifications

• 4+ years of experience in penetration testing, security assessment, or similar roles.
• Hands-on experience with pentesting platforms and tools (Kali or another dedicated OS; Burp Professional, Nmap, Metasploit, sqlmap, AMASS, etc.).
• Knowledge of OWASP Top 10 and familiarity with API, thick client, and LLM/AI attack surfaces.
• Experience with AI models and frameworks (e.g., OpenAI, Anthropic) and tooling (Obsidian, Ollama) is a plus.
• Scripting skills and working knowledge of at least one programming language and framework.
• Ability to work with diverse stakeholders and manage concurrent initiatives with good judgement and prioritization.
• Strong written and verbal communication skills in English; Spanish native or fluent is a plus.

Responsibilities

• Execute penetration testing engagements across multiple attack surfaces: web applications, APIs, networks, mobile, thick clients and AI/LLM-based systems.
• Design and perform automated and manual tests, producing clear, actionable, and prioritized findings for technical and non-technical audiences.
• Use and adapt testing platforms and tools (e.g., Kali Linux, Burp Suite, Nmap, Metasploit, sqlmap, AMASS, Postman/Swagger).
• Apply AI and LLM techniques (prompt engineering, agents, emerging frameworks) to accelerate reconnaissance and to generate or refine testing scripts.
• Develop, maintain, and validate AI-driven agents and tools to automate recurring testing tasks, reducing false positives and improving accuracy.
• Evaluate and integrate emerging AI-assisted offensive security tools into the team’s methodologies and playbooks.
• Create and maintain technical documentation, methodologies, and standard operating procedures (SOPs).
• Communicate service capabilities and test results effectively to clients and global stakeholders.

Skills

Penetration testing

Security assessment

Scripting

English communication

Team collaboration

Tools

Kali Linux

Burp Suite

Nmap

Metasploit

sqlmap

AMASS

Postman/Swagger

Job description

Deloitte is seeking a Senior Penetration Tester to join the Global Cyber Services team in Madrid. You will execute testing across web apps, APIs, networks, mobile and AI/LLM-based systems, delivering clear findings and actionable recommendations.

Ideal candidates have 4+ years in pen testing, hands-on tooling experience (Kali, Burp, Nmap, Metasploit, sqlmap, AMASS) and familiarity with OWASP Top 10. Strong English skills are required; Spanish fluency is a plus.