Who we are
About Threshold
Founder and principal consultant
Thomas O'Donnell
Threshold Security is run by Thomas O'Donnell, a penetration tester with over eight years of hands-on experience across the full stack of offensive security disciplines: infrastructure, web applications, cloud environments, wireless and physical security.
Physical assessments have been a consistent part of that work. Getting past the door is rarely the hard part. The interesting findings are what happens after: how far you can move, what you can access, and whether anyone notices. Those findings are what drive the work here.
Threshold Security exists to offer that same rigour as a standalone service, with clear reporting that clients can actually use.
Professional standing
- CSTMCyber Scheme Team Member
- CHECKCurrently operating at CHECK Team Member level
- SCSecurity cleared; details available where appropriate
Individual qualifications and role are shown for transparency. Threshold Security does not claim organisational CHECK-approved status.
Background
8+ years in offensive security
Conducting penetration tests across infrastructure, web applications, cloud platforms, wireless networks, and physical environments since 2018.
Physical engagements
Multiple successful physical penetration tests completed: perimeter bypass, access control, social engineering, and post-access movement.
Red team methodology
Work informed by red team principles: full kill-chain thinking, not just finding an open door but understanding what that door leads to.
How we work
Confidentiality
Every engagement operates under a strict NDA. Findings, methodology, and client identity are never disclosed.
Written authorisation
All work is conducted under a signed rules of engagement document. Nothing happens without documented client approval.
No surprises
Scope, timing, and methodology are agreed in advance. The report reflects what was agreed. No scope creep, no unexpected findings sprung at the end.
Let's talk
Tell us about your site and what you're looking to understand. A scoping call costs nothing.
Get in touch