On-premise & data center/06advanced14 min

ZEUS on-premise: reverse-SSH tunnel + scanning AD/ADFS and LDAP, vCenter, WinRM

This is the key lesson for anyone deploying ZEUS in an on-premise environment. It ties together everything from the previous lessons: AD/LDAP, vCenter, WinRM and tunneling — showing how the connector safely reaches into the customer's network without opening its firewall.

Access model: reverse-SSH tunnel

Inside the customer's network we deploy a lightweight collector (a container or a machine). It accepts no inbound connections. Instead it initiates an outbound reverse-SSH connection itself to the ZEUS control point:

# Collector wystawia kanał sterujący przez wychodzące SSH (port 443/22)
ssh -N -R 0:localhost:0 \
    -o ServerAliveInterval=30 -o ExitOnForwardFailure=yes \
    zeus-tunnel@relay.zeus.professnet.pl

Tip: the only connection is outbound traffic on 443/22 — identical to ordinary internet traffic. The customer's network team does not have to open any port "inward," which radically simplifies the security sign-off.

All further scanning traffic goes through this encrypted tunnel, within the customer's network, to the local systems.

Scan 1: AD/ADFS and LDAP — full domain, paging

Through the tunnel, ZEUS queries the domain controllers over LDAPS from a dedicated read-only service account. The key point: a paged search (pages of ~1000 objects with a continuation cookie), to read the full domain and not just the first batch:

  • users, groups, computers, service accounts,
  • membership in privileged groups (Domain Admins, etc.),
  • password hygiene (accounts with no expiration, PASSWD_NOTREQD),
  • Kerberoasting risk (service accounts with an SPN).

In addition, ZEUS checks the ADFS configuration (identity federation) where it is deployed — relying parties, claim rules, certificates.

Scan 2: vCenter / vSphere

Through the vSphere API (pyVmomi) and a Read-only account, ZEUS inventories the full VM fleet and the ESXi hosts: power state, guest OS, resources, VMware Tools, networks and host hardening (see lesson 02).

Scan 3: WinRM (the Windows fleet)

Through WinRM (HTTPS) and a read-only domain account, ZEUS collects the endpoint posture of Windows hosts — exclusively Get-*: patch level, local administrators, services and their accounts, the firewall state (see lesson 03).

Everything read-only

Scan targetProtocolPermissions
AD/ADFS/LDAPLDAPS (paged)read-only service account
vCenter/ESXivSphere APIRead-only role
WindowsWinRM HTTPSdomain account, only Get-*
Transportreverse-SSH (outbound)dedicated key

The connector has no permissions to modify anything — it physically cannot change anything in the customer's environment.

One view, regardless of location

The data from AD, vCenter and Windows flows into the same model as Azure, AWS and GCP. A machine in the customer's server room and a VM in the cloud land in one inventory, with one findings queue and one set of compliance evidence (NIS2, DORA, ISO 27001).

Track summary

From AD/LDAP, through vCenter, WinRM, networking and tunneling, to hybrid with Arc and the full on-prem connector — you now have the complete picture for understanding how ZEUS safely "sees" a customer's on-premise environment without opening its firewall.