CDXE
A free, open-source toolkit for running realistic cyber defence training exercises, simulating a mini version of the internet — routing, DNS, and all — from a single program.
🔗 Visit CDXE
Description
Training a security team to respond to real attacks usually requires setting up a realistic network to attack and defend, which normally means wrangling multiple pieces of infrastructure software just to simulate basic things like internet routing and DNS. CDXE packages all of that into one deployable tool, so organizations without a large IT team can still run believable cyber defence exercises.
It's a free, open-source tool built by Kryptogram AB in Go and deployed as a single statically-compiled binary, supporting full IPv4 and IPv6 with BGP peering, live environment modifications during an exercise, and WireGuard integration for secure network access. It's specifically designed for smaller-to-medium-scale exercises rather than nation-state-level simulations.
💬 Our review
The short version: if your organization wants to run a cyber defence exercise without months of infrastructure setup, CDXE's single-binary deployment is a free and refreshingly low-friction way to get a realistic training environment running.
Against Immersive Labs and HackTheBox, both commercial platforms offering broader content libraries, guided labs, and enterprise support (typically custom or subscription pricing), CDXE is a much more DIY, infrastructure-focused tool — you're simulating your own network and scenario rather than working through a pre-built curriculum. That's an advantage if you need a custom, realistic exercise environment specific to your organization, and a disadvantage if you want ready-made training content and a support contract. The main real gaps are the absence of a clear commercial support model and English-only documentation aimed squarely at a technical audience.
📊 Global score
🤖 AI-enriched data
Gratuit et open source.
Pros
Déploiement simple via binaire unique
Support complet IPv4/IPv6 avec BGP
Modifications en temps réel
Intégration WireGuard
Optimisé exercices petite/moyenne échelle
Cons
Pas de modèle commercial clair
Documentation anglaise uniquement
Communauté potentiellement restreinte