Proxmox Security Hardening — from default to production-ready
A standard Proxmox installation is not production-secure. MFA, granular RBAC, firewall segmentation, audit logging and CVE monitoring are not options — they are mandatory. We harden your cluster according to BSI recommendations and CIS Benchmark.
Leading companies worldwide trust WZ-IT
The following are trademarks of their respective owners: Proxmox VE (Proxmox Server Solutions GmbH). WZ-IT is an independent service provider and has no business, partnership, or contractual relationship with these companies. We offer independent migration, installation, hosting, and operations services.
What Proxmox security covers
Defense in depth — no single measure protects you. We combine six layers of protection into a robust security concept.
Authentication & MFA
TOTP/WebAuthn for all admin accounts, OIDC/SAML integration with Authentik or Keycloak, separate read/write roles.
Firewall & Network Segmentation
Proxmox firewall at cluster, node and VM level. Separation of management, storage and VM networks via VLAN/SDN.
API Tokens & Service Accounts
Granular API tokens with scope limitation, rotation, revocation. No root tokens for automation.
CrowdSec / Fail2Ban
Protection against brute-force attacks on SSH and web UI. CrowdSec for collaborative threat intelligence network.
Audit Logging & SIEM
Complete audit trail of all admin actions. SIEM integration via Syslog/Wazuh for compliance and forensics.
CVE Monitoring & Patching
Continuous monitoring for vulnerabilities in PVE, kernel and guest OS. Automated patching workflows with maintenance windows.
Concrete measures, no platitudes
What we concretely implement in every cluster hardening — at cluster, VM and backup level.
Cluster & Host
- SSH hardening (key-only, port change, rate limiting)
- Kernel parameters hardened via sysctl
- AppArmor/SELinux policies active
- Subscription notice removed, repos hardened
- Web UI only reachable via VPN/bastion
VMs & Containers
- Unprivileged containers as default
- CPU pinning against L1TF/Spectre
- IOMMU isolation for PCI passthrough
- Disk encryption (LUKS, ZFS native)
- Cloud-init with signed templates
Backup & Recovery
- PBS with client-side encryption
- Air-gapped/immutable offsite copy
- Object lock on S3 backend (PBS 4.2)
- Quarterly restore validation
- Ransomware tabletop exercise
Where does your cluster stand?
Before we harden, we do a structured security audit of your existing setup. You get a report with concrete findings, prioritized by risk, and an action plan with effort estimate.
Cluster configuration
PVE, Corosync, quorum
Network & firewall
VLAN, SDN, FW rules
IAM & permissions
RBAC, MFA, API tokens
Backup & recovery
PBS, offsite, restore tests
Patching & CVEs
Update status, known CVEs
Audit logs
Logging, SIEM, retention
Not "insecure" but not production-grade. Defaults: no MFA, web UI on port 8006 public, firewall disabled, minimal audit logging. OK for internal lab environments, unacceptable for production (especially with GDPR data). We typically harden 30-50 configuration points per cluster.
A complete security audit (cluster configuration, network, IAM, backup, patching, logging) costs from €1,490. You receive a detailed report with prioritized findings, risk assessment and concrete action plan. Implementation of findings is optional as hourly retainer or fixed-price project.
Our hardening measures are based on BSI Grundschutz, CIS Benchmark for Linux, Proxmox Security Hardening Guide and Proxmox community best practices. For regulated industries we map to BSI C5, ISO 27001 or specific requirements (BaFin, KRITIS).
The Proxmox firewall blocks unauthorized network access — yes, that helps against lateral movement. But ransomware typically comes through VMs (phishing, web exploits) — the VM/workload firewall protects there. The most important ransomware protection: client-side encrypted, immutable offsite backups via PBS 4.2 with S3 object lock.
Best practice: security updates within 14 days of release, critical CVEs (CVSS ≥9) within 72 hours. We handle patching within our maintenance service levels — automated updates with maintenance windows and rollback plan.
We offer white-box audits with configuration review, not classic pentest. For external pentesting we cooperate with certified pentest firms — we coordinate the scope, document the findings and implement remediation.
Industry-leading companies rely on us
What do our customers say?
Let's Talk About Your Idea
Whether a specific IT challenge or just an idea – we look forward to the exchange. In a brief conversation, we'll evaluate together if and how your project fits with WZ-IT.
Trusted by leading companies
Timo Wevelsiep & Robin Zins
Managing Directors of WZ-IT