nuDefend — cyber protection for your cloud servers
A single command installs a lightweight agent that shows what your server exposes and where it connects, and blocks known attackers inbound and outbound. Privacy-first, self-updating, no logs or traffic collected.
14 days free, no credit card required. Your trial starts only when the agent connects to the server.
curl -sSL https://get.nudefend.com | sudo bash -s <YOUR_LICENSE_KEY>Runs on any Linux server — AWS, Azure, GCP, DigitalOcean or on-prem. Replace <YOUR_LICENSE_KEY> with the key from your welcome email.
How it works
Install in seconds
One command installs the signed, secure nuDefend agent onto your server. No dashboard to babysit.
Maps the server
From the first minutes the agent records what is listening, which of it is reachable from outside, and which destinations the AI tools on the server connect to — containers included.
Blocks known attackers
A cryptographically signed threat list refreshes every 30 minutes. Traffic to and from malicious addresses and domains is dropped at the kernel firewall, before it reaches your services.
The rest is your call
Exposure you did not intend closes from the dashboard or in one command, after a preview of exactly what will be blocked. Reports never leave the server.
Why nuDefend
Any cloud, any server
AWS, Azure, GCP, DigitalOcean, bare metal — if it runs Linux, it's protected.
Privacy-first
Everything is processed on your server. Your logs and your traffic never leave it.
Always fresh
Threat lists refresh automatically every 30 minutes, so protection never goes stale.
Self-healing
The agent monitors itself and restores its rules if anything tampers with them.
Secure and hardened
A compact, hardened nuDefend agent — no embedded secrets and no needless attack surface.
One-line install
No agents to configure, no console to learn. Paste one command and you're done.
You cannot protect what you cannot see
nuDefend answers three questions before it blocks anything for you: what your server exposes, where it connects, and what you want closed.
What your server exposes
Every service accepting connections from outside, containers included, with the unusual one raised above the routine and an alert the moment something becomes reachable that was not before.
See what is reachableWhere your server connects
A compromised AI tool usually calls out. nuDefend records which destinations each tool reaches, names them where it recognises them, and shows how much data went to each one — so an unusual destination stands out instead of hiding in a list of numbers.
See what leavesClose what should not be open
Nothing is blocked unless you ask for it, every change is previewed first, and one click undoes it. The connection you are logged in through cannot be blocked at all.
See how closing worksWhat nuDefend blocks
Two independent layers guard every server — one at the network edge, one at the DNS level — so threats are stopped whether they arrive, leave, or try to resolve a dangerous name.
Network layer — malicious IPs
Traffic to and from known-bad addresses is dropped at the kernel firewall, before it ever reaches the services on your server.
DNS layer — malicious domains
Dangerous domains are blackholed system-wide, so no application on the server can resolve or reach them.
AI crawlers & aggressive bots
A new wave of AI scrapers and automated crawlers hammers origins around the clock, burning CPU, bandwidth and database connections. nuDefend keeps pace — its threat lists refresh every 30 minutes, so protection tracks the shifting AI bot landscape and drops the worst offenders at the server itself.
How nuDefend protects your origin from AI crawlersBlock entire countries
Cut your exposure in one click. Choose exactly which countries can reach your server, or which ones cannot. Country blocking is included free with every nuDefend license.
Open (default)
Every country is allowed. Your server stays reachable worldwide, while malicious IPs and domains are still blocked as always.
Allow list
Only the countries you pick can connect. Perfect when your users live in a handful of regions and everywhere else is just noise.
Block list
Everyone connects except the countries you choose. A one-click high-risk countries shortcut blocks the usual sources of attacks instantly.
Safe by design
nuDefend never blocks the country your server sits in, so you cannot lock yourself out. Rules apply in both directions and reverse the moment you switch back to Open.
Simple per-server pricing
Pay only for the servers you protect. Cancel anytime.
- Unlimited blocklist updates
- Inbound + outbound protection
- Reports stay on your server — no logs or traffic collected
- Email support
14 days free, no credit card required. Your trial starts only when the agent connects to the server.
Available on AWS Marketplace
Subscribe to nuDefend directly through AWS Marketplace and pay on your existing AWS bill — one-click provisioning, cancel anytime.
Privacy by design
No security data leaves your server — no logs, no traffic, no reports, ever. Reports are generated on your machine and stay there.
Outbound traffic is limited to two things: a licence check every 30 minutes, and downloading the signed threat lists and agent updates, which are served over a content delivery network. The licence check sends your licence key, the agent version and a one-way hash of the machine ID. Like any internet request it arrives from your server's IP address, and we keep that address with the licence record, together with the agent version and when the server last checked in, to enforce the number of servers you bought. That is the complete list — there is nothing else.
Fair and transparent
If a subscription lapses, nuDefend fails open — it stops blocking rather than locking you out — and can cleanly uninstall itself. No lock-in, ever.