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+# Security Policy
+
+## Supported Versions
+
+We take the security of OpenIsle seriously. The following versions are currently being supported with security updates:
+
+| Version | Supported          |
+| ------- | ------------------ |
+| 0.0.x   | :white_check_mark: |
+
+## Reporting a Vulnerability
+
+We appreciate your efforts to responsibly disclose your findings and will make every effort to acknowledge your contributions.
+
+### How to Report a Security Vulnerability
+
+**Please do not report security vulnerabilities through public GitHub issues.**
+
+Instead, please report them via one of the following methods:
+
+1. **Email**: Send a detailed report to the project maintainer (check the repository for contact information)
+2. **GitHub Security Advisory**: Use GitHub's private vulnerability reporting feature at https://github.com/nagisa77/OpenIsle/security/advisories/new
+
+### What to Include in Your Report
+
+To help us better understand the nature and scope of the issue, please include as much of the following information as possible:
+
+- Type of issue (e.g., SQL injection, XSS, authentication bypass, etc.)
+- Full paths of source file(s) related to the manifestation of the issue
+- The location of the affected source code (tag/branch/commit or direct URL)
+- Any special configuration required to reproduce the issue
+- Step-by-step instructions to reproduce the issue
+- Proof-of-concept or exploit code (if possible)
+- Impact of the issue, including how an attacker might exploit it
+
+### Response Timeline
+
+- **Initial Response**: We will acknowledge your report within 48 hours
+- **Status Updates**: We will provide status updates at least every 5 business days
+- **Resolution**: We aim to resolve critical vulnerabilities within 30 days of disclosure
+
+### What to Expect
+
+After you submit a report:
+
+1. We will confirm receipt of your vulnerability report and may ask for additional information
+2. We will investigate the issue and determine its impact and severity
+3. We will work on a fix and coordinate disclosure timing with you
+4. Once the fix is ready, we will release it and publicly acknowledge your contribution (unless you prefer to remain anonymous)
+
+## Security Considerations for Deployment
+
+### Authentication & Authorization
+
+- **JWT Tokens**: Ensure `JWT_SECRET` environment variable is set to a strong, random value (minimum 256 bits)
+- **OAuth Credentials**: Keep OAuth client secrets secure and never commit them to version control
+- **Session Management**: Configure appropriate session timeout values
+
+### Database Security
+
+- Use strong database passwords
+- Never expose database ports publicly
+- Use database connection encryption when available
+- Regularly backup your database
+
+### API Security
+
+- Enable rate limiting to prevent abuse
+- Validate all user inputs on both client and server side
+- Use HTTPS in production environments
+- Configure CORS properly to restrict origins
+
+### Environment Variables
+
+The following sensitive environment variables should be kept secure:
+
+- `JWT_SECRET` - JWT signing key
+- `GOOGLE_CLIENT_SECRET` - Google OAuth credentials
+- `GITHUB_CLIENT_SECRET` - GitHub OAuth credentials
+- `DISCORD_CLIENT_SECRET` - Discord OAuth credentials
+- `TWITTER_CLIENT_SECRET` - Twitter OAuth credentials
+- `WEBPUSH_PRIVATE_KEY` - Web push notification private key
+- Database connection strings and credentials
+- Cloud storage credentials (Tencent COS)
+
+**Never commit these values to version control or expose them in logs.**
+
+### File Upload Security
+
+- Validate file types and sizes
+- Scan uploaded files for malware
+- Store uploaded files outside the web root
+- Use cloud storage with proper access controls
+
+### Password Security
+
+- Configure password strength requirements via environment variables
+- Use bcrypt or similar strong hashing algorithms (already implemented in Spring Security)
+- Implement account lockout after failed login attempts
+
+### Web Push Notifications
+
+- Keep `WEBPUSH_PRIVATE_KEY` secret and secure
+- Only send notifications to users who have explicitly opted in
+- Validate notification payloads
+
+### Dependency Management
+
+- Regularly update dependencies to patch known vulnerabilities
+- Run `mvn dependency-check:check` to scan for vulnerable dependencies
+- Monitor GitHub security advisories for this project
+
+### Production Deployment Checklist
+
+- [ ] Use HTTPS/TLS for all connections
+- [ ] Set strong, unique secrets for all environment variables
+- [ ] Enable CSRF protection
+- [ ] Configure secure headers (CSP, X-Frame-Options, etc.)
+- [ ] Disable debug mode and verbose error messages
+- [ ] Set up proper logging and monitoring
+- [ ] Implement rate limiting and DDoS protection
+- [ ] Regular security updates and patches
+- [ ] Database backups and disaster recovery plan
+- [ ] Restrict admin access to trusted IPs when possible
+
+## Known Security Features
+
+OpenIsle includes the following security features:
+
+- JWT-based authentication with configurable expiration
+- OAuth 2.0 integration with major providers
+- Password strength validation
+- Protection codes for sensitive operations
+- Input validation and sanitization
+- SQL injection prevention through ORM (JPA/Hibernate)
+- XSS protection in Vue.js templates
+- CSRF protection (Spring Security)
+
+## Security Best Practices for Contributors
+
+- Never commit credentials, API keys, or secrets
+- Follow secure coding practices (OWASP Top 10)
+- Validate and sanitize all user inputs
+- Use parameterized queries for database operations
+- Implement proper error handling without exposing sensitive information
+- Write security tests for new features
+- Review code for security issues before submitting PRs
+
+## Disclosure Policy
+
+When we receive a security bug report, we will:
+
+1. Confirm the problem and determine affected versions
+2. Audit code to find any similar problems
+3. Prepare fixes for all supported versions
+4. Release patches as soon as possible
+
+We appreciate your help in keeping OpenIsle and its users safe!
+
+## Attribution
+
+We believe in recognizing security researchers who help improve OpenIsle's security. With your permission, we will acknowledge your contribution in:
+
+- Security advisory
+- Release notes
+- A security hall of fame (if established)
+
+If you prefer to remain anonymous, we will respect your wishes.
+
+## Contact
+
+For any security-related questions or concerns, please reach out through the channels mentioned above.
+
+---
+
+Thank you for helping keep OpenIsle secure!