Service Line · Cybersecurity & Offensive Security

Cybersecurity &
Offensive Security

Adversarial testing, scoped against the real-world exposure our intelligence work surfaces. Single engagement letter. Single point of accountability. Accredited specialist delivery under Greyline's scoping and quality control.

Cybersecurity & Offensive Security

Adversarial testing, scoped against your real exposure.


Greyline's intelligence work surfaces the exposure that matters; our cybersecurity engagements test what an attacker would actually attempt against it. Every engagement is scoped jointly with the delivery specialist, conducted under signed rules of engagement, and reported in a format the client's executive and technical teams can both act on. Greyline retains the client relationship, intelligence-led scoping, reporting standard, and single point of accountability throughout.

Penetration Testing

External, internal, web application, and infrastructure penetration testing scoped to the client's environment. Authorised, controlled, and documented to standards that satisfy regulator and insurer requirements. Delivered by accredited testers (CREST, OSCP, CISSP equivalents) under Greyline's intelligence-led scoping and project management, with findings interpreted against business risk rather than handed off as a raw scanner output.

Quoted post-inquiry
Suited for: regulated firms with periodic testing obligations, organisations responding to cyber-insurance requirements, businesses handling sensitive client data, and any organisation needing evidential assurance over its real-world security posture.

Vulnerability Assessment

Authenticated and unauthenticated vulnerability assessment of internal systems, external-facing assets, and cloud configurations. Findings are interpreted, prioritised against business risk, and tracked to remediation — not delivered as a raw scanner output that no one acts on. Where pen testing is the next step, the assessment is structured to feed directly into scoping.

Quoted post-inquiry
Suited for: organisations needing a clear picture of technical exposure across their estate, businesses preparing for penetration testing or cyber-insurance, and clients responding to regulatory requirements for periodic assessment.

Social Engineering Assessment

Authorised social engineering assessments testing the human layer of organisational security — pretext-based approaches, voice-based attacks, physical access attempts, and combined campaigns. Conducted under written rules of engagement with full ethical and legal safeguards. Results are anonymised, structured for executive reporting, and tied to training outcomes.

Quoted post-inquiry
Suited for: organisations with high-value targets (executives, finance teams, compliance functions), businesses recovering from a social engineering incident, and any client whose technical controls are robust but whose human layer has not been formally tested.
How specialist delivery works

One engagement letter, one accountable party.


Greyline scopes the engagement, selects the appropriate accredited delivery specialist, manages the project end-to-end, and is the client's single point of accountability. The technical work is performed by tested specialist firms with the relevant accreditations (CREST, OSCP, CISSP and equivalents); the intelligence-led scoping, reporting standard, and client relationship sit with us.

This protects clients from the cost and risk of unaccredited vendors, while ensuring that cybersecurity findings are integrated with the broader intelligence picture Greyline maintains for the client. Clients sign a single engagement agreement with Greyline; specialist relationships are managed by us.

Begin a Cybersecurity Engagement

Scope a cybersecurity engagement.

Every cybersecurity engagement is scoped jointly with the delivery specialist before pricing. Submit a confidential inquiry and we will arrange a 30-minute scoping call.