Bastion Talent is retained by a specialist cybersecurity firm working in critical infrastructure to fill this role. Our client works with large organisations — operators, governments and enterprises — to find and fix serious security weaknesses. The client’s identity is shared with shortlisted candidates under NDA.
Engagement & location
This position is fully remote within Europe (CET overlap preferred). Unless otherwise stated, it can be structured either as a freelance / contract engagement or as full-time employment — whichever suits you.
About the client
Our client is a specialist cybersecurity firm and a recognised leader in offensive security for critical infrastructure. They help large organisations — operators, governments and major enterprises — find and fix serious weaknesses in the systems that keep essential services running, pairing hands-on security assessment with their own detection and analysis tooling. The team is small, highly technical and fully distributed across Europe.
The role
Conduct security assessments and penetration testing across telecom network infrastructure, and help design and deploy secure telecom systems.
Key responsibilities
- Deep, hands-on work across SS7, SIGTRAN, Diameter, LTE, IMS and GTP-C and their security weaknesses.
- Run security assessments and penetration tests on telecom network infrastructure.
- Develop and implement defensive solutions against network attacks and intrusions.
- Collaborate across teams to design and deploy secure telecom systems.
- Stay current with telecom security research, tooling and techniques.
What we’re looking for
- Strong understanding of telecom network architecture and protocols.
- Demonstrated mastery of SS7, Diameter, LTE and IMS.
- Experience running security assessments and penetration tests.
- Knowledge of telecom security best practice and standards.
- Excellent analytical and communication skills.
- Fluent English (mandatory); French optional.
Environment & specialisations
VoLTE, VoWiFi, GTP, NFV(i), S1AP, X2AP, NGAP, PFCP, 5GC SBI and fuzzing; OpenStack / Kubernetes / Linux server exposure a plus.
Hiring process
- Intro call (10–20 min)
- Manager call (30 min)
- Capability exercise
- Leadership call (30 min)