About
Founder-led adversary validation for organizations that need evidence, not assumptions.
Offensive Guardian is a founder-led offensive-security consultancy for mature organizations. We design and execute threat-informed adversary simulation, red-team, purple-team, and detection-validation engagements that produce decision-grade evidence.
What we are
- A founder-led offensive-security consultancy
- Threat-informed adversary emulation, red team, and purple team
- Detection validation and continuous offensive assurance
- Every finding tied to evidence, an owner, and a retest
What we are not
- A commodity penetration-testing shop
- A scan-and-report vulnerability factory
- A junior bench sold behind a senior pitch
- A report that creates work without telling you what to fix first
The person you meet is the person who runs the engagement.
Offensive Guardian is led by Jean-François Maes. He is the lead author of SANS SEC565: Red Team Operations and Adversary Emulation, co-author of SEC699: Advanced Purple Teaming, and a SANS Certified Instructor. He has worked for reputable security firms including NVISO, TrustedSec, and Fortra, where he was a Cobalt Strike researcher, with over a decade of hands-on offensive operations behind him. His open-source tooling, including LazySign, SharpZipRunner, and TrustJack, is used by red teams worldwide.
Most testing ends with a list. The useful work starts one step later: proving how the defense behaved while it mattered, and making the fix stick. That is the only work I do.
How we operate
Offensive Guardian LLC is a Delaware company working with clients across the EU, UK, and North America. We work under a mutual NDA as standard, and data handling and retention are agreed per engagement before any access.