About this role
“I am hugely excited about my future and the future of CyberOne. I have enjoyed my time here immensely and have learnt a huge amount in a short space of time, year-for-year I've learnt more here than I have at Microsoft and PwC.” - CyberOne Consultant
About CyberOne
CyberOne is a pure-play Microsoft security partner dedicated to helping enterprises realise the full value of the Microsoft Security portfolio—across Defender XDR, Sentinel, Entra, Purview, Intune, Copilot for Security and more. We combine deep technical expertise with outcome-driven services that accelerate secure cloud adoption, modernise threat protection and simplify compliance.
Job Title: Penetration Tester
Location: Remote
Employment Type: Full-time
We are seeking a highly skilled and motivated Penetration Tester to join our Cyber Security team. The successful candidate will be responsible for conducting advanced penetration testing engagements across enterprise environments, with a particular focus on Active Directory (AD) security assessments. This role requires hands-on experience identifying, exploiting, and documenting security vulnerabilities while providing practical remediation recommendations to strengthen clients' security posture.
Key Responsibilities
Conduct comprehensive penetration testing engagements against enterprise infrastructure, networks, systems, and applications.
Perform manual and automated security assessments to identify vulnerabilities, weaknesses, and potential attack vectors.
Assess and exploit Active Directory environments, identifying security risks including:
Misconfigurations
Privilege escalation paths
Lateral movement opportunities
Credential theft vulnerabilities
Excessive permissions and insecure delegation
Execute network and system exploitation activities to validate security weaknesses and assess their impact.
Evaluate the effectiveness of security controls, hardening measures, and defensive configurations within Active Directory environments.
Simulate real-world attack scenarios to assess organizational resilience against cyber threats.
Develop detailed technical reports outlining attack paths, findings, business impact, proof-of-concept evidence, and remediation recommendations.
Present technical findings to both technical and non-technical stakeholders.
Work closely with internal teams and clients to support remediation efforts and provide security best-practice guidance.
Stay up to date with emerging threats, attack techniques, exploitation methodologies, and security technologies.
Required Skills & Experience
Proven experience conducting penetration tests across enterprise networks and infrastructure.
Strong knowledge of Windows environments and Active Directory security.
Experience identifying and exploiting Active Directory vulnerabilities and attack paths.
Excellent understanding of:
Network protocols and architecture
Windows Server administration
Authentication mechanisms (Kerberos, NTLM)
Privilege escalation techniques
Lateral movement methodologies
Hands-on experience with penetration testing and red team tools such as:
BloodHound
Mimikatz
CrackMapExec
Impacket
Nmap
Burp Suite
Metasploit
Responder
Familiarity with vulnerability assessment and security testing methodologies including OWASP, NIST, and PTES.
Strong technical documentation and report-writing skills.
Excellent analytical, troubleshooting, and problem-solving abilities.
Preferred Qualifications
Offensive Security Certified Professional (OSCP)
CRTO (Certified Red Team Operator)
CREST Registered Penetration Tester (CRT) or CREST Certified Infrastructure Tester (CCT INF)
GIAC Penetration Tester (GPEN)
Relevant Microsoft security certifications
Experience delivering internal or external client-facing security assessments