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SECURITY.md

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+<!--
+ Copyright (C) 2026 Moko Consulting <hello@mokoconsulting.tech>
+ SPDX-License-Identifier: GPL-3.0-or-later
+-->
+
+# Security Policy
+
+## Supported Versions
+
+| Version | Supported |
+|---|---|
+| Latest stable | ✅ Full support |
+| Previous major | ⚠️ Critical fixes only |
+| Older | ❌ No support |
+
+## Reporting a Vulnerability
+
+**Do not report security vulnerabilities via public issues.**
+
+Instead, please report them privately:
+
+1. **Email**: [security@mokoconsulting.tech](mailto:security@mokoconsulting.tech)
+2. **Subject**: `[SECURITY] <Repository Name> - <Brief Description>`
+
+### What to Include
+
+- Description of the vulnerability
+- Steps to reproduce
+- Affected versions
+- Potential impact
+- Suggested fix (if any)
+
+## Severity Classification
+
+| Severity | Description | Response Time |
+|---|---|---|
+| **Critical** | Remote code execution, SQL injection, auth bypass | 24 hours |
+| **High** | XSS, CSRF, privilege escalation | 48 hours |
+| **Medium** | Information disclosure, path traversal | 72 hours |
+| **Low** | Best practice violation, hardening suggestion | Next release |
+
+## Remediation Timeline
+
+1. **Acknowledgement**: Within 24 hours of report
+2. **Assessment**: Within 72 hours
+3. **Fix development**: Based on severity
+4. **Release**: Patch release with security advisory
+5. **Disclosure**: Coordinated disclosure after fix is available
+
+## Security Best Practices
+
+### For Contributors
+
+- Never commit secrets, credentials, or API keys
+- Use parameterised queries (no raw SQL concatenation)
+- Validate and sanitise all user input
+- Follow Joomla API for access control checks
+- Use Joomla's `HTMLHelper` for output escaping
+- Include SPDX license headers in all source files
+
+### For Users
+
+- Keep Joomla and all extensions updated
+- Use strong, unique passwords
+- Enable two-factor authentication
+- Review file permissions regularly
+- Monitor Joomla error logs
+
+## Security Updates
+
+Security patches are delivered through the standard update channel.
+Critical fixes may receive an emergency out-of-band release.
+
+## Responsible Disclosure
+
+We follow coordinated disclosure practices:
+
+- We will work with reporters to understand and reproduce the issue
+- We will develop and test a fix
+- We will credit reporters (with permission) in security advisories
+- We ask that reporters allow reasonable time for a fix before public disclosure
+
+## Contact
+
+- **Security team**: [security@mokoconsulting.tech](mailto:security@mokoconsulting.tech)
+- **General**: [hello@mokoconsulting.tech](mailto:hello@mokoconsulting.tech)
+
+---
+
+Thank you for helping keep Moko Consulting projects secure.