Catalog
concept#Security#Platform#Architecture

Server Security

Principles and measures to protect servers, operating systems, services and hosted applications from unauthorized access and tampering.

Server security encompasses practices and controls to protect server systems, their operating systems, services, and hosted applications from compromise.
Established
Medium

Classification

  • Medium
  • Technical
  • Architectural
  • Intermediate

Technical context

Identity provider / IAM (e.g. LDAP, SSO)SIEM and log aggregation (e.g. Elastic, Splunk)Configuration management & orchestration (e.g. Ansible, Terraform)

Principles & goals

Minimal attack surface: enable only necessary services.Verify before trust: regular integrity checks and audits.Automate repeatable hardening steps.
Run
Enterprise, Domain, Team

Use cases & scenarios

Compromises

  • Misconfigurations can impair availability or functionality.
  • Incomplete inventory leads to unpatched hosts.
  • Excessive centralization can create single points of failure.
  • Use versioned, vetted base images.
  • Automated patch testing in staging before production rollout.
  • Least privilege principle for service and user accounts.

I/O & resources

  • Inventory of servers and operating systems
  • Security policies and compliance requirements
  • Access and role models
  • Hardened base images and configuration templates
  • Auditable logs and monitoring dashboards
  • Patch and compliance reports

Description

Server security encompasses practices and controls to protect server systems, their operating systems, services, and hosted applications from compromise. It combines hardening, patch management, access control, logging and network protections to reduce attack surface and ensure integrity, confidentiality and availability of server workloads.

✔

  • Reduced attacker entry points through standardized hardening.
  • Improved compliance and traceability via documented configurations.
  • Faster incident response due to centralized monitoring and playbooks.

✖

  • Not all attacks can be prevented by hardening alone.
  • Hardening may cause compatibility issues with legacy applications.
  • Requires ongoing maintenance and resources for patching and monitoring.

  • Patch compliance rate

    Ratio of patched systems versus inventoried systems.

  • Mean time to detect (MTTD)

    Average time between incident and initial detection.

  • Mean time to repair (MTTR)

    Average time to recovery after a security incident.

Linux server hardening in a SaaS product

Applying CIS benchmarks, central patch management and role-based access control for production servers.

On-premise web server with WAF and logging

Web server behind WAF, centralized log aggregation and regular penetration tests to detect vulnerabilities.

Cloud VM profiling and image management

Versioned hardened VM images, minimal service footprint and automated scanning before deployments.

1

Perform inventory and risk analysis; derive policies.

2

Create base images, apply hardening profiles and automate.

3

Set up monitoring, alerting and regular compliance checks.

⚠️ Technical debt & bottlenecks

  • Manually maintained configuration files without version control.
  • Legacy images not regularly updated.
  • Ad-hoc hardening scripts instead of reproducible automation.
Manual effort in configuration managementOutdated inventory prevents timely patchesBottlenecks in security expertise within ops team
  • Hardening without tests that breaks legitimate functions.
  • Deploying critical patches without a rollback plan in production windows.
  • Centralized locks without emergency access cause outages.
  • Overspecifying policies that restrict flexibility.
  • Underestimating effort for inventory and automation.
  • Lack of monitoring for exception rules and temporary exceptions.
Operating system and network fundamentalsKnowledge of hardening and patch processesExperience with monitoring and forensic tools
Integrity and confidentiality of critical dataAvailability of production workloadsRegulatory requirements and compliance
  • • Legacy applications with tight compatibility requirements
  • • Limited maintenance windows in production environments
  • • Organizational acceptance of restrictions