Offensive Security Consultant

Mantel; City of Melbourne; Hybrid; AUD 100,000 - 140,000; Full time

Benefits offered by this job

New device and tools provided

My Deal program

Family Inclusive Workplace

AI-enabled career development

Flexible personal leave

Hybrid work arrangements

Internal opportunities across domains

Job summary

Mantel, an Australian-owned IT professional services consultancy, is seeking an Offensive Security Consultant to join its cyber security team in Melbourne. You will conduct penetration tests, analyse security gaps, and improve client security posture through hands-on assessments and clear reporting.

Ideal candidates have experience across network, web and mobile testing, strong code-reading skills, and the ability to communicate complex findings to both technical and non-technical stakeholders.

Qualifications

• Experience running multiple types (network/web/mobile) penetration tests for customers.
• Foundational understanding of networking, operating systems, and web security principles.
• Ability to review application source code to identify security issues in business logic and authentication.
• Excellent written and verbal communication, able to explain technical concepts to diverse audiences.
• Strong analytical skills with a keen eye for vulnerabilities and risk.
• Aligned with Mantel’s five principles and collaborative culture.

Responsibilities

• Conduct large-scale and targeted penetration tests for enterprise clients.
• Test client applications, networks and systems to identify vulnerabilities.
• Perform blackbox, greybox and whitebox testing with source code assistance where applicable.
• Document findings and remediation actions clearly for clients.
• Contribute to detailed reports summarising risks and recommendations.
• Communicate findings to clients in technical and non-technical terms.

Skills

Penetration testing

Networking basics

Security assessment

Tools

Burp Suite

Metasploit

Nmap

Job description

Mantel is an Australian-owned IT Professional Services consultancy, focused on emerging technology to help advance our clients by leveraging AI, Digital, Cloud, Data & Security technology. We are a fully AI-enabled technology consultancy and the partner that bridges the gap between blue-sky ambition and practical steps to deliver value. Since our inception in November 2017, we have experienced remarkable growth across Australia & New Zealand and are honoured to be recognised as a Great Place to Work for 7 years in a row!

We hire smart and talented people and get out of their way. As a principle-based organisation, we have a flat structure with no hierarchy. By focusing on our five principles and not getting caught up in red tape, we trust you to get the job done!

Working in our growing cyber security capability allows you to work closely with clients across our teams. Our security capabilities span governance, risk and compliance, cyber engineering, and offensive security. We enable large-scale cyber security initiatives for our clients, and improve the protection of IT environments.

About the role:

As an Offensive Security Consultant at Mantel, you will be an integral part of our cybersecurity team, helping to identify and mitigate security vulnerabilities for our clients. In this role, you will conduct penetration tests, analyse security gaps and work alongside experienced professionals to improve the security posture of client systems. This is an ideal role for a detail-oriented individual looking to develop their skills in ethical hacking and security assessment.

Your day to day:

• Work on both large scale and targeted penetration testing projects for enterprise customers
• Conduct penetration tests on client applications (web/mobile/desktop), networks and systems to identify vulnerabilities and weaknesses
• Work on a mix of blackbox, greybox and whitebox source code assisted penetration tests
• Perform vulnerability assessments using various tools and techniques, then document findings and suggest remediation actions
• Contribute to detailed reports that summarise findings, prioritise risks, and provide actionable recommendations for improving security
• Communicate findings to clients in both technical, and clear non-technical manners and work with them to understand security requirements and potential impacts
• Provide offensive security experience and recommendations across a wide range of technologies and solutions, including conducting security reviews
• Stay current with the latest vulnerabilities, exploits, and cybersecurity trends. Contribute to the team’s continuous improvement efforts by researching new tools and methodologies

What you’ll need to be successful:

• Experience running multiple types (network/web/mobile) of penetration tests for customers
• Foundational understanding of networking, operating systems, and common web application security principles. Knowledge of penetration testing tools (e.g., Burp Suite, Metasploit, Nmap) is essential
• Ability to review and understand application source code to identify security issues in business logic, authentication and authorisation, input handling, and data processing
• Excellent written and verbal communication skills, with the ability to explain technical concepts to both technical and non-technical audiences
• Strong analytical skills with a keen eye for identifying vulnerabilities and weaknesses in complex systems
• At Mantel, we want you to be yourself. We trust our team members to use their professional judgment while treating colleagues and clients with respect, compassion, and professionalism in alignment with our five principles
• You take ownership, always stepping up to help and prioritising your teammates. You're also a clear, kind communicator who makes sound decisions based on good judgement

Highly desirable skills:

• Experience in AI pen testing and using AI security tools
• Ability to write code in modern programming languages
• Ability to use coding skills during security testing, including writing scripts, tooling, and proof-of-concept code to support white-box and code-assisted penetration testing

What you can expect from us:

• You’ll get all the tools you need to hit the ground running including a new phone, laptop & swag.
• We believe in unique experiences for all. Our My Deal program allows you to tailor your yearly plan, with the support of your Leader, to decide on what’s most important to you. That might be extra professional development, extra annual leave, time to work on your side hustle, or something else completely different! One size does not fit all.
• Mantel is a certified Family Inclusive Workplace, which means we are committed to improving your wellbeing at work through leading practices on flexible work, parental leave, family care and family wellbeing
• A true investment in your AI-first career. We are a fully AI-enabled consultancy and provide you with the tools to lead. This includes access to the Mantel AI Gateway, our secure, centralised platform with multiple AI models, plus a dedicated monthly budget and a safe environment to experiment and innovate.
• You’ll be genuinely supported by an organisation that cares about not only you but your family as well, Mantel offers Flexible Personal Leave options for those unplanned moments in life.
• We support a flexible hybrid approach to working which is guided by our principles; we trust each other to “make good choices” about the best workplace locations for the requirements of the project, role and client. This can change based on our client needs.
• We know you won’t have one job for life. At Mantel, we believe in supporting our team to take their career in a direction that aligns with their passions. We have internal opportunities across Cloud, Data, Digital, Delivery & Security.
• Our elite partnerships are a direct result of our deep platform mastery. For you, this means you'll be working alongside teams with the highest levels of technical expertise and tackling the most complex, high-profile projects on the market. Check out our partner awards and recognitions here.

We value a diverse workplace and strongly encourage people from all backgrounds and minority groups to apply.