Server Hardening Review

Review of Linux server hardening including SSH security, firewall rules, user management, service minimization and access controls.

What Server Hardening Covers

A Server Hardening Review evaluates how well your Linux server has been locked down against common attack vectors. We review your configuration against established hardening benchmarks and real-world attack patterns.

Our review covers:

  • SSH hardening — disabled root login, key-based authentication enforced, non-standard port, allowed users/groups, idle timeout, protocol version
  • Firewall rules — default deny policy, minimal allowed inbound, egress filtering, IPv6 rules, rule organization
  • User management — inactive accounts, password aging, shell restrictions, service account lockdown, umask settings
  • Sudo policy — least-privilege assignments, NOPASSWD usage, sudoers file hygiene, logging of sudo commands
  • Service minimization — unnecessary services disabled, startup daemons reviewed, listening sockets reduced to what is required
  • Kernel parameters — sysctl hardening (IP forwarding, SYN cookies, ICMP redirects, core dumps, address space layout randomization)
  • File permissions — world-writable files, SUID/SGID binaries, sensitive file permissions (/etc/shadow, /etc/ssh/), tmp directory restrictions
  • Automatic updates — unattended-upgrades or equivalent, security-only update channels, reboot policy
  • Intrusion detection — fail2ban configuration, ban thresholds, monitored services, log-based alerting
  • Audit and logging — auditd rules, log integrity, centralized logging, retention policies

Common Gaps We Find

Even well-managed servers frequently have hardening gaps:

  • SSH allows password authentication alongside keys
  • Firewall permits outbound traffic without restriction
  • Sudo grants broad privileges to multiple users or uses NOPASSWD
  • Fail2ban monitors SSH only, ignoring web and mail services
  • SUID binaries remain from default installations
  • Kernel parameters left at distribution defaults without tuning
  • Automatic security updates not enabled or not verified

What You Receive

  • A hardening assessment report with current configuration vs. recommended baseline
  • Risk-rated findings with clear severity levels
  • Step-by-step remediation instructions for each gap
  • A prioritized action plan based on risk and implementation effort
  • Follow-up consultation to walk through the findings

Get Started

Review our pricing or contact us to schedule a server hardening review.

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