System Security

1. Overview

The system is deployed within the organization’s internal infrastructure and managed by the IT and Security teams.

Security for CostOS is enforced through a defense-in-depth strategy that includes:

• User access control and identity management

• Network and host security

• Data encryption

• Continuous monitoring and auditing

• Regular patching and security reviews

This document defines the technical and procedural security controls required to protect CostOS and its underlying infrastructure.

2. System Architecture

CostOS follows a three-tier architecture:

1. Presentation Layer (Front-End):
   Web interface served via Apache HTTP Server hosted on internal servers.

2. Application Layer (Business Logic):
   Middleware and API services responsible for processing business rules.

3. Data Layer (Storage):
   Local or network-attached databases and file systems used for storing configuration and user data.

Each layer operates on separate servers or virtual machines, protected by network segmentation and access controls.

3. User Access & Identity Management

3.1 Authentication & Single Sign-On (SSO)

CostOS supports multiple authentication mechanisms suitable for self-hosted enterprise environments:

• LDAP / Active Directory Integration:
  Users authenticate using their corporate Windows credentials.
  The system binds to the organization’s LDAP directory for account lookup and validation.

• Kerberos Authentication:
  Integrated Windows Authentication (IWA) is supported for seamless single sign-on within the internal network.
  Kerberos tickets are used to validate user sessions securely without transmitting passwords.

• SAML 2.0 / OpenID Connect (OIDC):
  CostOS can integrate with external identity providers such as Azure AD, Okta, or Keycloak to provide federated SSO.
  This allows centralized access management and multi-factor authentication (MFA).

All authentication traffic is encrypted over TLS 1.2+ to prevent credential interception.

3.2 Role-Based Access Control (RBAC)

User roles determine system privileges and access scope.
Permissions are designed around the principle of least privilege to minimize risk of unauthorized data exposure.

3.3 Account Management

• Accounts are automatically synchronized or created via LDAP directory or SAML/OIDC provisioning.

• Account modifications and removals are tied to HR processes.

3.4 Session Management

User sessions are:

• Protected with signed and encrypted tokens

• Bound to user identity and device

• Subject to session timeouts and idle logout policies

• Secured with HTTPOnly, Secure, and SameSite cookie attributes

4. Network & System Security

4.1 Network Segmentation

Only necessary ports and protocols are allowed between tiers.

4.2 Firewalls

Perimeter and internal firewalls restrict traffic between CostOS servers and external networks.
Rules are reviewed quarterly to ensure least-privilege access.

4.3 Server Hardening

All servers hosting CostOS components must be hardened according to organizational standards:

• Disable unused services and ports

• Enforce OS-level firewalls

• Apply the latest security patches and updates

• Regularly scan for vulnerabilities using internal tools

4.4 Security Headers

The Apache web server must be configured with:

• Content-Security-Policy (CSP)

• X-Frame-Options: DENY

• X-Content-Type-Options: nosniff
  These headers protect the web interface against clickjacking and injection attacks.

5. Data Security & Encryption

5.1 Encryption in Transit

All communications between clients, application servers, and databases must be encrypted using TLS 1.2 or higher.

SSL/TLS Certificate Installation

• A valid SSL/TLS certificate must be installed on the Apache web server hosting CostOS.

• Certificates must:

  • Be issued by a trusted internal or public Certificate Authority (CA)

  • Use a SHA-256 or stronger signature algorithm

  • Be renewed before expiration (automatic renewal or renewal tracking required)

  • Be stored securely with restricted access to private keys

  • Enforce HTTPS-only access (redirect all HTTP requests to HTTPS)

• Self-signed certificates may be used only for development or internal testing environments and must not be deployed in production.

5.2 Encryption at Rest

• 5.2 Encryption at Rest

  • Sensitive information stored in databases (such as credentials, personal data) is encrypted using strong symmetric encryption algorithms (e.g., AES-256 or other approved standards).

  • Administrators can define or rotate the encryption keys used by CostOS to secure sensitive data.

  • The application supports custom encryption key definitions, allowing organizations to align with their internal cryptographic policies or regulatory frameworks.

  • The encryption algorithm and key management policy can be configured in the application settings or external key management module.

  • Encryption keys are stored securely (not within the database) and are accessible only to authorized system processes.

6. Application Security

6.1 Input Validation & Sanitization

All user inputs are validated to prevent SQL injection, XSS, CSRF, and other common web vulnerabilities.

6.2 Secure Configuration

• Default credentials and unnecessary modules are removed before deployment.

• Configuration files containing secrets or credentials are stored outside the web root and protected with strict file permissions.

6.3 Code Review & Testing

• Code undergoes peer review before release.

• Static and dynamic application security testing tools are used to identify vulnerabilities prior to deployment.

7. Monitoring & Auditing

7.1 System Logging

• CostOS generates detailed audit logs for authentication events, configuration changes, administrative actions, and data access.

• Logs are forwarded to a centralized Syslog or SIEM server for correlation, monitoring, and long-term retention.

7.2 Security Auditing

Quarterly audits are conducted to verify:

• Compliance with internal security policies

• Server patching status

• Certificate validity and configuration integrity

7.3 Incident Response

An incident response plan must exist to:

• Detect and classify incidents

• Contain and remediate impacts

• Document findings and corrective actions

8. Integrated Security Tools

8.1 Vulnerability Scanning

Periodic vulnerability scans are performed on servers and application components using internal scanning tools.

8.2 Dependency and Code Scanning

Automated tools are integrated into the build process to detect insecure libraries.

8.3 Security Updates

Patches are applied according to severity:

• Critical: within 24–48 hours

• High: within 5 business days

• Medium/Low: as part of regular maintenance

9. Compliance & Security Best Practices

• Aligns with ISO 27001, NIST SP 800-53, and OWASP Top 10 principles.

• Adheres to company IT policies on access control, encryption, and incident management.

• Annual penetration testing is conducted by internal or third-party teams.

• All administrators and users receive annual cybersecurity awareness training.

10. Server Certificate & HTTPS Management

• The Apache web server hosting the CostOS presentation layer must enforce HTTPS-only connections.

• System administrators are responsible for:

  • Installing, renewing, and validating SSL/TLS certificates

  • Restricting file access to private keys and configuration files

  • Monitoring certificate expiration and renewal logs

12. Conclusion

CostOS enforces a layered, defense-in-depth security model across its self-hosted environment.
Through strict access control, encryption, patching, and continuous monitoring, CostOS maintains a secure operational posture that protects organizational data and ensures business continuity.