sec-design-deep-analysis.md

Deep Security Analysis of Metabase - Open Source Business Intelligence Tool

1. Objective, Scope, and Methodology

Objective:

The primary objective of this deep security analysis is to thoroughly evaluate the security posture of Metabase, an open-source business intelligence tool, based on its architecture, components, and data flow as outlined in the provided security design review document. This analysis aims to identify potential security vulnerabilities, assess associated risks, and provide actionable, Metabase-specific mitigation strategies to enhance the overall security of Metabase deployments. The analysis will focus on key security domains including authentication, authorization, data source security, web application security, API security, data privacy, infrastructure security, and dependency management.

Scope:

This security analysis encompasses the following aspects of Metabase, as described in the security design review document:

• System Architecture: Client Tier (Web Browser), Application Tier (Metabase Application Server), and Data Tier (Metabase Metadata Database, Connected Data Sources).
• Data Flow: Analysis of the query execution data flow to understand data processing and potential interception points.
• Security Considerations: Detailed examination of authentication and authorization mechanisms, data source security, web application security, API security, data privacy, infrastructure security, and dependency management as outlined in section 5 of the design review.
• Technology Stack: Review of the technologies used in Metabase (Java/Clojure, React, databases, etc.) to identify technology-specific security concerns.
• Deployment Options: Consideration of security implications across different deployment scenarios (self-hosted, cloud).

The analysis is limited to the information presented in the security design review document and publicly available information about Metabase as of October 2023. It does not include dynamic testing, penetration testing, or source code review.

Methodology:

This deep security analysis will be conducted using the following methodology:

1. Document Review and Understanding: A thorough review of the provided security design review document to gain a comprehensive understanding of Metabase's architecture, components, data flow, and identified security considerations.
2. Component-Based Security Analysis: Decomposition of Metabase into its key components (Client Tier, Application Tier, Data Tier, Authentication, Authorization, API, etc.) and analyzing the security implications of each component individually and in interaction with others.
3. Threat Modeling (Implicit Approach): Leveraging the threat modeling focus of the security design review, we will implicitly perform threat modeling by analyzing each security consideration area and inferring potential threats and vulnerabilities based on common attack vectors and security best practices.
4. Vulnerability Identification and Risk Assessment: Identifying potential vulnerabilities within each component and assessing the associated risks based on potential impact and likelihood of exploitation.
5. Tailored Mitigation Strategy Development: Developing specific, actionable, and tailored mitigation strategies for each identified vulnerability. These strategies will be directly applicable to Metabase's architecture and functionalities, focusing on practical and implementable solutions.
6. Recommendation Prioritization: Prioritizing mitigation strategies based on the severity of the identified risks and the feasibility of implementation, considering the open-source nature of Metabase and its user base.

2. Security Implications of Key Components and Mitigation Strategies

Based on the security design review, we will now analyze the security implications of each key component and provide tailored mitigation strategies.

2.1. Authentication and Authorization:

Security Implications:

• Username/Password (Local DB):
  • Threat: Brute-force attacks, credential stuffing, dictionary attacks. If weak passwords are used or no rate limiting is in place, attackers can gain unauthorized access.
  • Threat: Compromised credentials leading to full account takeover and access to sensitive data and Metabase functionalities.
• LDAP/Active Directory, Google OAuth/SAML SSO:
  • Threat: Reliance on external systems means security is dependent on the configuration and security of these external providers. Misconfigurations or vulnerabilities in these systems can lead to unauthorized access to Metabase.
  • Threat: Account takeover if the external SSO provider is compromised or if there are vulnerabilities in the integration with Metabase.
• API Tokens:
  • Threat: Insecure generation, storage, or rotation of API tokens can lead to token compromise and unauthorized API access.
  • Threat: Stolen API tokens can be used to bypass authentication and perform actions programmatically, potentially leading to data breaches or system manipulation.
• RBAC Misconfiguration:
  • Threat: Overly permissive roles or incorrectly assigned permissions can grant users unintended access to data or functionalities.
  • Threat: Privilege escalation (horizontal or vertical) if vulnerabilities exist in the RBAC implementation or if roles are not properly managed.
• Data Source Permission Sync Issues:
  • Threat: Discrepancies between Metabase permissions and underlying data source permissions can lead to users bypassing Metabase's access controls and directly accessing data sources with insufficient authorization logging.

Mitigation Strategies:

• Strengthen Password Policies:
  • Action: Enforce strong password policies (minimum length, complexity, expiration) for local database authentication. Metabase should provide configuration options to customize these policies.
  • Action: Encourage and document best practices for password management for Metabase administrators and users.
• Implement Rate Limiting and Account Lockout:
  • Action: Implement rate limiting on login attempts to mitigate brute-force attacks. Metabase should automatically lock out accounts after a certain number of failed login attempts.
  • Action: Provide configuration options for administrators to customize rate limiting and lockout thresholds.
• Multi-Factor Authentication (MFA):
  • Action: Implement and encourage the use of MFA for all authentication methods, especially for administrative accounts and access to sensitive data. Explore integrating MFA options beyond SSO providers, potentially through plugins or extensions.
  • Action: Clearly document how to enable and configure MFA for different authentication methods in Metabase.
• Regular Security Audits of RBAC:
  • Action: Conduct regular audits of roles and permissions to identify and rectify any misconfigurations or overly permissive access.
  • Action: Provide tools within Metabase to easily review and manage user permissions and role assignments. Implement a principle of least privilege by default.
• Secure API Token Management:
  • Action: Ensure API tokens are generated using cryptographically secure methods.
  • Action: Store API tokens securely (hashed and salted in the metadata database).
  • Action: Implement token rotation and expiration policies. Provide mechanisms for users to easily revoke and regenerate tokens.
  • Action: Document best practices for API token security, emphasizing secure storage and transmission.
• Centralized Authentication and Authorization:
  • Action: For production environments, strongly recommend using robust external authentication providers like LDAP/AD or SSO (SAML/OAuth) for centralized user management and enhanced security.
  • Action: Provide clear documentation and guides for integrating Metabase with various authentication providers.
• Permission Synchronization and Enforcement:
  • Action: Develop mechanisms to better synchronize and enforce permissions between Metabase and connected data sources where feasible. This might involve leveraging data source native permission models or developing connector-specific permission mapping.
  • Action: Clearly document the limitations of permission synchronization and advise administrators to configure appropriate access controls directly on the data sources as well.

2.2. Data Source Security:

Security Implications:

• Credential Storage in Metadata Database:
  • Threat: If the Metabase metadata database is compromised, data source connection credentials (even if encrypted) could be exposed, leading to unauthorized access to connected data sources.
  • Threat: Insecure encryption methods or weak key management for stored credentials can weaken protection.
• Connection String Injection:
  • Threat: If connection string parameters are not properly sanitized, attackers could inject malicious parameters to manipulate the connection, potentially leading to unauthorized access or data breaches.
• SQL/NoSQL Injection:
  • Threat: Vulnerabilities in query generation or allowing raw SQL/NoSQL queries can lead to injection attacks, allowing attackers to execute arbitrary code on the database, bypass security controls, access or modify data, or perform denial-of-service attacks.
• Data Exfiltration via Queries:
  • Threat: Authorized users with sufficient permissions could craft queries to exfiltrate large amounts of sensitive data, even if access controls are in place.
• JDBC/Driver Vulnerabilities and Malicious Drivers:
  • Threat: Vulnerabilities in JDBC drivers or native connectors can be exploited for remote code execution or other attacks.
  • Threat: Supply chain attacks involving malicious drivers could compromise Metabase and connected data sources.

Mitigation Strategies:

• Enhanced Credential Encryption and Key Management:
  • Action: Utilize robust encryption algorithms (e.g., AES-256) for encrypting data source credentials at rest in the metadata database.
  • Action: Implement secure key management practices, such as using a dedicated key management system (KMS) or securely storing encryption keys outside of the application codebase.
  • Action: Regularly review and update encryption methods and key management practices to align with security best practices.
• Connection String Parameter Sanitization:
  • Action: Implement strict input validation and sanitization for all connection string parameters to prevent connection string injection attacks.
  • Action: Use parameterized queries or prepared statements when constructing database connection strings to avoid direct string concatenation of user-supplied input.
• Parameterized Queries and Input Sanitization for Query Generation:
  • Action: Ensure that Metabase's query builder and SQL editor use parameterized queries or prepared statements to prevent SQL and NoSQL injection vulnerabilities.
  • Action: Implement robust input validation and sanitization for all user-supplied inputs used in query generation, especially when allowing raw SQL queries.
  • Action: Consider using a query parser and analyzer to detect and prevent potentially malicious or dangerous SQL queries.
• Query Execution Monitoring and Auditing:
  • Action: Implement comprehensive logging and auditing of all database queries executed by Metabase, including user, query details, and data source accessed.
  • Action: Monitor query execution patterns for anomalies that might indicate data exfiltration attempts or malicious activity.
  • Action: Consider implementing query execution limits or restrictions based on user roles or data sensitivity to mitigate data exfiltration risks.
• JDBC/Driver Security Management:
  • Action: Maintain an inventory of all JDBC drivers and native connectors used by Metabase.
  • Action: Regularly update JDBC drivers and connectors to the latest versions to patch known vulnerabilities. Implement a process for tracking and applying security updates for drivers.
  • Action: Verify the integrity and authenticity of JDBC drivers and connectors to mitigate supply chain risks. Consider using driver repositories with security scanning and verification processes.
  • Action: Document recommended and tested JDBC driver versions for each supported database to guide users towards secure configurations.
• Least Privilege Data Source Access:
  • Action: Encourage users to configure data source connections with the principle of least privilege. Metabase connection accounts should only have the necessary permissions to perform required operations (e.g., SELECT for read-only access).
  • Action: Provide guidance and documentation on how to configure least privilege access for different data source types.

2.3. Web Application Security:

Security Implications (OWASP Top 10):

• Cross-Site Scripting (XSS):
  • Threat: Unsanitized user input displayed in the web interface can lead to XSS vulnerabilities, allowing attackers to inject malicious scripts to steal session cookies, redirect users, or deface the application.
• Cross-Site Request Forgery (CSRF):
  • Threat: Lack of CSRF protection can allow attackers to trick authenticated users into performing unintended actions on Metabase, such as modifying dashboards, adding users, or changing settings.
• SQL Injection (Revisited):
  • Threat: As previously discussed, SQL injection remains a web application vulnerability if not properly mitigated in query generation and raw SQL handling.
• Insecure Deserialization:
  • Threat: If Metabase deserializes untrusted data, it could be vulnerable to insecure deserialization attacks, potentially leading to remote code execution.
• Security Misconfiguration:
  • Threat: Default configurations, exposed administrative interfaces, or unnecessary services can create attack vectors.
• Insufficient Logging and Monitoring:
  • Threat: Lack of adequate logging and monitoring hinders incident detection, response, and forensic analysis.

Mitigation Strategies:

• Robust Output Encoding and Input Sanitization (XSS Prevention):
  • Action: Implement robust output encoding for all user-supplied data displayed in the web interface to prevent XSS vulnerabilities. Use context-aware encoding based on where the data is being displayed (HTML, JavaScript, URL, etc.).
  • Action: Sanitize user input where necessary, but prioritize output encoding as the primary defense against XSS.
  • Action: Regularly scan the application for XSS vulnerabilities using automated security scanning tools.
• Implement CSRF Protection:
  • Action: Implement CSRF protection mechanisms (e.g., synchronizer tokens) for all state-changing requests to prevent CSRF attacks.
  • Action: Ensure CSRF protection is enabled by default and properly configured across the application.
• Secure Query Generation and Parameterized Queries (SQL Injection Prevention):
  • Action: Reinforce the use of parameterized queries and prepared statements throughout the application to prevent SQL injection.
  • Action: Conduct regular code reviews and security testing to identify and remediate any potential SQL injection vulnerabilities.
• Avoid Insecure Deserialization:
  • Action: Avoid deserializing untrusted data whenever possible. If deserialization is necessary, use safe deserialization methods and carefully validate the data being deserialized.
  • Action: Regularly audit and update libraries and frameworks used for serialization and deserialization to patch known vulnerabilities.
• Harden Security Configurations:
  • Action: Implement secure default configurations for Metabase.
  • Action: Disable or restrict access to administrative interfaces to authorized users and networks only.
  • Action: Remove or disable unnecessary services and features to reduce the attack surface.
  • Action: Regularly review and update security configurations based on security best practices and security hardening guides.
• Comprehensive Logging and Monitoring:
  • Action: Implement comprehensive logging for all security-relevant events, including authentication attempts, authorization decisions, data access, configuration changes, and errors.
  • Action: Integrate Metabase logs with a centralized logging and monitoring system (SIEM) for real-time monitoring, alerting, and incident response.
  • Action: Establish clear procedures for monitoring logs, detecting security incidents, and responding to alerts.
• Regular Security Scanning and Penetration Testing:
  • Action: Conduct regular automated security scans (SAST/DAST) to identify web application vulnerabilities.
  • Action: Perform periodic penetration testing by qualified security professionals to simulate real-world attacks and identify vulnerabilities that automated scans might miss.

2.4. API Security:

Security Implications:

• API Authentication and Authorization Bypass:
  • Threat: Vulnerabilities in API authentication or authorization mechanisms could allow unauthorized access to API endpoints and functionalities, leading to data breaches or system manipulation.
• API Rate Limiting and DoS:
  • Threat: Lack of rate limiting on API endpoints can make Metabase susceptible to denial-of-service attacks, impacting availability and performance.
• API Input Validation:
  • Threat: Insufficient input validation on API requests can lead to various vulnerabilities, including injection attacks, data manipulation, and unexpected application behavior.

Mitigation Strategies:

• Robust API Authentication and Authorization:
  • Action: Enforce strong authentication for all API endpoints, using mechanisms like API tokens, OAuth 2.0, or JWT.
  • Action: Implement granular authorization controls for API endpoints, ensuring that only authorized users or applications can access specific API functionalities and data.
  • Action: Regularly review and test API authentication and authorization mechanisms for vulnerabilities.
• API Rate Limiting and Throttling:
  • Action: Implement rate limiting on API endpoints to prevent denial-of-service attacks and API abuse.
  • Action: Configure rate limits based on API endpoint sensitivity and expected usage patterns.
  • Action: Provide mechanisms for administrators to customize rate limits and manage API usage.
• Strict API Input Validation:
  • Action: Implement strict input validation for all API requests, validating data types, formats, and ranges.
  • Action: Sanitize and encode API input data to prevent injection attacks.
  • Action: Use API schemas and validation frameworks to enforce input validation rules consistently across the API.
• API Security Auditing and Logging:
  • Action: Log all API requests, including authentication details, request parameters, and responses, for security auditing and incident investigation.
  • Action: Monitor API logs for suspicious activity, such as unauthorized access attempts, excessive requests, or unusual data patterns.
  • Action: Integrate API logs with a centralized logging and monitoring system (SIEM).
• API Documentation and Security Guidelines:
  • Action: Provide comprehensive API documentation that includes security considerations, authentication methods, authorization models, and input validation requirements.
  • Action: Publish API security guidelines for developers and users to promote secure API usage.

2.5. Data Privacy and Compliance:

Security Implications:

• Lack of Data Masking/Anonymization:
  • Threat: Displaying sensitive data without masking or anonymization can violate data privacy regulations (GDPR, HIPAA, CCPA, etc.) and expose sensitive information to unauthorized users.
• Data Residency and Location:
  • Threat: Storing or processing data in regions that do not comply with data residency requirements of regulations can lead to legal and compliance issues.
• Inadequate Audit Logging for Compliance:
  • Threat: Insufficient audit logging can hinder compliance with regulations requiring audit trails of data access and processing, making it difficult to demonstrate compliance and investigate security incidents.

Mitigation Strategies:

• Implement Data Masking and Anonymization Features:
  • Action: Develop and integrate data masking and anonymization features into Metabase to allow users to mask or anonymize sensitive data fields in visualizations and reports.
  • Action: Provide configuration options to define data masking rules based on data sensitivity and user roles.
  • Action: Document how to use data masking and anonymization features to comply with data privacy regulations.
• Data Residency Considerations and Deployment Guidance:
  • Action: Provide clear guidance and documentation on data residency considerations for Metabase deployments.
  • Action: Advise users to choose deployment locations and data source locations that comply with relevant data privacy regulations.
  • Action: Explore features or configurations that can help users control data residency, such as data source connection configurations or deployment options in specific regions.
• Enhanced Audit Logging for Compliance:
  • Action: Expand audit logging capabilities to capture all security-relevant events required for compliance with data privacy regulations (e.g., GDPR, HIPAA, CCPA).
  • Action: Ensure audit logs include sufficient detail, such as user identity, timestamp, action performed, data accessed, and outcome.
  • Action: Provide configuration options for administrators to customize audit logging levels and retention policies to meet compliance requirements.
  • Action: Document audit logging capabilities and how they can be used for compliance purposes.

2.6. Infrastructure Security:

Security Implications:

• Operating System Vulnerabilities:
  • Threat: Unpatched operating systems hosting Metabase servers are vulnerable to OS-level exploits, potentially leading to server compromise and data breaches.
• Network Security Misconfigurations:
  • Threat: Open ports, weak firewall rules, or insecure network configurations can expose Metabase to network-based attacks.
• Vulnerable Dependencies:
  • Threat: Vulnerabilities in third-party libraries and dependencies used by Metabase can be exploited for remote code execution or other attacks.
• Supply Chain Attacks:
  • Threat: Compromised dependencies or build pipelines could introduce malicious code into Metabase, potentially leading to widespread compromise.
• Insecure Deployment Practices:
  • Threat: Using default configurations, running Metabase with excessive privileges, or exposing unnecessary services can increase the attack surface and create vulnerabilities.
• Lack of Security Updates:
  • Threat: Failure to apply security updates and patches promptly leaves Metabase vulnerable to known exploits.

Mitigation Strategies:

• Operating System Hardening and Patch Management:
  • Action: Harden the operating systems hosting Metabase servers by applying security best practices, such as disabling unnecessary services, configuring strong access controls, and implementing intrusion detection systems.
  • Action: Establish a robust patch management process to regularly apply security updates and patches to the operating system and all installed software.
  • Action: Use automated patch management tools to streamline the patching process and ensure timely updates.
• Network Security Hardening:
  • Action: Implement strong firewall rules to restrict network access to Metabase servers to only necessary ports and protocols.
  • Action: Use network segmentation to isolate Metabase servers from other less secure network segments.
  • Action: Regularly review and audit network security configurations to identify and remediate misconfigurations.
  • Action: Consider using a Web Application Firewall (WAF) to protect Metabase from web-based attacks.
• Dependency Management and Vulnerability Scanning:
  • Action: Maintain a Software Bill of Materials (SBOM) for Metabase to track all dependencies.
  • Action: Use dependency scanning tools to regularly scan Metabase dependencies for known vulnerabilities.
  • Action: Establish a process for promptly updating vulnerable dependencies to patched versions.
  • Action: Consider using dependency management tools that provide vulnerability alerts and automated updates.
• Secure Software Development Lifecycle (SSDLC) and Supply Chain Security:
  • Action: Implement a secure software development lifecycle (SSDLC) that incorporates security considerations at every stage of development, from design to deployment.
  • Action: Implement measures to secure the software supply chain, such as verifying the integrity and authenticity of dependencies, using secure build pipelines, and performing code signing.
  • Action: Conduct regular security code reviews and penetration testing to identify and remediate vulnerabilities early in the development process.
• Secure Deployment Practices and Hardening Guides:
  • Action: Develop and publish secure deployment guides and hardening checklists for Metabase, covering various deployment environments (self-hosted, cloud).
  • Action: Recommend and enforce secure deployment practices, such as using non-root user accounts, minimizing exposed services, and disabling default accounts.
  • Action: Provide configuration templates and scripts for secure deployments.
• Regular Security Updates and Patching for Metabase:
  • Action: Establish a process for promptly releasing and communicating security updates and patches for Metabase.
  • Action: Encourage users to subscribe to security advisories and apply security updates in a timely manner.
  • Action: Provide clear instructions and tools for applying security updates.

3. Conclusion

This deep security analysis of Metabase, based on the provided security design review, has identified key security considerations across various components and functionalities. By implementing the tailored mitigation strategies outlined above, the development team can significantly enhance the security posture of Metabase, reduce the risk of potential vulnerabilities being exploited, and improve data privacy and compliance. It is crucial to prioritize these recommendations based on risk severity and implement them as part of an ongoing security improvement program for Metabase. Continuous security monitoring, regular security assessments, and proactive vulnerability management are essential to maintain a strong security posture for Metabase in the evolving threat landscape.