Deloitte logo
Deloitte

senior penetration tester @thessaloniki

Nov 13, 2026 · Deloitte

Νομός Θεσσαλονίκης·Nov 13, 2026
Νομός ΘεσσαλονίκηςHybridΠληροφορικήPermanentFull Time
JOBILY AI SUMMARY

What you'll do

  • Lead and deliver penetration testing and offensive security assessments across applications, infrastructure, networks, cloud platforms, and enterprise environments.
  • Identify, validate, and exploit vulnerabilities while assessing technical risk and business impact within agreed scope.
  • Apply recognized security methodologies and frameworks throughout the assessment lifecycle.
  • Prepare actionable reports, present findings to stakeholders, and support remediation prioritization and tracking.
  • Mentor junior team members, review technical outputs, and improve offensive security methodologies, tools, and delivery quality.

Key requirements

  • 3+ years' experience
  • Offensive security & penetration testing across web applications, APIs, infrastructure, networks, cloud platforms, and mobile applications.
  • Vulnerability identification and exploitation, including hands-on assessment and validation.
  • Security methodologies and frameworks, including OWASP, NIST, PTES, and MITRE ATT&CK.
  • Scripting and code analysis with Python and Bash.
  • Burp Suite, Nmap, and Metasploit.
  • OSCP certification and security reporting skills.
  • Information Technology / Computer and Data Science / Business Informatics / Engineering / Information Systems Management / Computer Science / Cybersecurity / Computer Engineering / Data Science / Other Relevant IT-Related Disciplinespreferred

Benefits

  • Modern hybrid workplace with flexible Smart Working arrangements, well-being programs, extra leave, parental allowances, international projects, travel opportunities, learning platforms, sponsored certificates, private medical insurance, restaurant card, mobile phone, discounts, and office refreshments.

About the job

Our Offensive Security Team specializes in identifying, testing, and breaching security boundaries to build unyielding resilience. We simulate sophisticated real-world attacks across hybrid infrastructures, cloud platforms, applications, networks, and complex enterprise environments to expose vulnerabilities before they can be exploited.

Quite simply, we provide the adversarial perspective, delivering rigorous penetration testing and red teaming engagements that stress-test our clients’ defenses and help them strengthen their security posture.

Join us and you could find yourself working on a broad range of offensive security assignments, from focused technical assessments to complex multi-domain penetration testing programs. These may include web applications, APIs, mobile applications, infrastructure, cloud platforms, containerized environments, network infrastructure, wireless networks, firewall and security gateways, source code reviews, thick clients, mainframe applications, telecommunication infrastructure, and risk-based penetration testing.

In short, you will break solutions to help our clients build them stronger, meeting evolving business requirements while contributing to the growth of the team through high-impact delivery, technical leadership, and thought leadership in the offensive security space.

#Core Responsibilities

·       Lead and deliver penetration testing and offensive security assessments across web applications, APIs, mobile applications, infrastructure, networks, cloud platforms, and other complex enterprise environments.

·       Perform hands-on vulnerability identification, validation, and exploitation, assessing technical risk and business impact in line with agreed scope and rules of engagement.

·       Apply recognized security methodologies and frameworks such as OWASP, NIST, PTES, and MITRE ATT&CK throughout the assessment lifecycle.

·       Prepare clear, actionable reports and present findings to technical and non-technical stakeholders, supporting clients in prioritizing and tracking remediation activities.

·       Mentor junior team members, review technical outputs, and contribute to the continuous improvement of offensive security methodologies, tools, and delivery quality.

#OurRequirements

  • Academic background (BSc and MSc) related to Information Technology, Computer and Data Science, Business Informatics, Engineering. We also welcome graduates with a business background, who have major in Information Systems Management or any other IT-related major.

  • Able to manage office automation tools, such as MS Excel, MS PowerPoint, MS Access

  • Excellent command of the Greek and English language

  • Very good knowledge of Italian and other languages will be considered a plus

  • Strong interest for Offensive Security with active participation in CTFs (e.g., Hack The Box, TryHackMe)

  • Theoretical knowledge of Cloud, Infrastructure, Mobile, API, and Web architectures from an offensive security and exploitation perspective.

  • Proficiency in scripting and code analysis (e.g., Python, Bash, C#) for exploit automation and vulnerability testing.

  • Relevant certifications such as OSCP (Offensive Security), CPTS (Hack The Box), or BSCP (PortSwigger) are highly preferred.

  • Analytic mindset

  • Good interpersonal and communication skills

  • Aptitude to the team working

  • Client Orientation

  • Academic background in Information Technology, Computer Science, Cybersecurity, Computer Engineering, Data Science, Business Informatics, Engineering, or other relevant IT-related disciplines.

  • Minimum 3 years of professional experience in penetration testing, offensive security, vulnerability assessment, red teaming, or similar cybersecurity roles.

  • OSCP certification is required.

  • Additional relevant certifications such as OSEP, OSWE, CPTS, CRTO, GPEN, GWAPT, eWPTX, eCPPT, CARTP, or BSCP will be considered a strong asset.

  • Hands-on experience across several penetration testing domains, such as web applications, APIs, mobile applications, infrastructure, networks, cloud platforms, operating systems, servers, containerized environments, wireless networks, or thick clients.

  • Strong knowledge of offensive security methodologies, vulnerability exploitation techniques, and security frameworks such as OWASP, NIST, MITRE ATT&CK, and related industry standards.

  • Experience with offensive security tools such as Burp Suite, Nmap, Metasploit, Nessus, BloodHound, Impacket, Cobalt Strike, or equivalent tools.

  • Proficiency in scripting and code analysis, for example with Python, Bash, PowerShell, C#, or other relevant languages used for automation, testing, and tooling.

  • Strong reporting, communication, and client-facing skills, with the ability to produce clear deliverables and interact effectively with technical teams and senior stakeholders.

  • Excellent command of the Greek and English language; knowledge of Italian or other languages will be considered a plus.

If you are ready to apply your offensive security expertise in a challenging international environment, contribute to high-impact projects, and collaborate with teams across Greece and abroad, you are ready for Deloitte!

#WhatWeOffer

At Deloitte, we know that great people make a great organization. We value our people and offer employees a broad range of benefits:

  • Modern hybrid workplace, characterized by flexibility and Smart Working

  • Empowered well-being: We provide multiple program offerings to support your well-being needs (flexible working arrangements, extra days of leave, parental allowances)

  • Engagement within international large-scale teams and projects, with opportunities to travel for training or client purposes.

  • Constant opportunities for learning with unlimited access to internal and external learning platforms and sponsored certificates aligned with business needs and technology trends

  • Challenging and innovating environment where personal development and growth are encouraged, always with transparency and trust

  • Diverse culture and active communities that enable you to bring yourself to work

  • Team Building and Corporate Social Responsibility Activities

  • A buddy to support you with your onboarding

  • Extra days of annual leave

  • Private medical health insurance plan

  • Ticket restaurant card

  • Exclusive Discounts to several retail providers, restaurants and others

  • Mobile phone

  • Fresh fruits and unlimited coffee everyday at our offices

About the company

Deloitte drives progress. Our firms around the world help clients become leaders wherever they choose to compete. Deloitte invests in outstanding people of diverse talents and backgrounds and empowers them to achieve more than they could elsewhere. Our work combines advice with action and integrity. We believe that when our clients and society are stronger, so are we.


Deloitte refers to one or more of Deloitte Touche Tohmatsu Limited (“DTTL”), its global network of member firms, and their related entities. DTTL (also referred to as “Deloitte Global”) and each of its member firms are legally separate and independent entities. DTTL does not provide services to clients. Please see www.deloitte.com/about to learn more.

Workplace
Hybrid
Sector
Πληροφορική
Employment Type
Permanent
Work Time
Full Time

About the company

Deloitte drives progress. Our firms around the world help clients become leaders wherever they choose to compete. Deloitte invests in outstanding people of diverse talents and backgrounds and empowers them to achieve more than they could elsewhere. Our work combines advice with action and integrity. We believe that when our clients and society are stronger, so are we.


Deloitte refers to one or more of Deloitte Touche Tohmatsu Limited (“DTTL”), its global network of member firms, and their related entities. DTTL (also referred to as “Deloitte Global”) and each of its member firms are legally separate and independent entities. DTTL does not provide services to clients. Please see www.deloitte.com/about to learn more.