threat-modeling.md

Threat Model Analysis for usememos/memos

Threat: Unintended Public Exposure of Private Memos

• Description: An attacker, either an external unauthorized user or a logged-in user without proper permissions, could gain access to memos intended to be private. This could happen due to bugs in the access control logic, misconfiguration of sharing settings, or unclear UI/UX leading to users unintentionally making memos public. An attacker might exploit these vulnerabilities by directly accessing API endpoints, manipulating URL parameters, or leveraging flaws in the permission checking mechanisms.
• Impact: Confidentiality breach. Sensitive information contained within private memos could be exposed to unauthorized individuals, leading to privacy violations, reputational damage, or potential legal repercussions depending on the nature of the exposed data.
• Affected Component: Access Control Module, Sharing Functionality, UI/UX related to privacy settings, API endpoints for memo retrieval.
• Risk Severity: High
• Mitigation Strategies:
  • Developers:
    • Implement robust and well-tested access control mechanisms with clear separation of public and private memos.
    • Conduct thorough security audits and penetration testing of access control logic and sharing features.
    • Ensure clear and intuitive UI/UX for setting memo privacy and sharing permissions.
    • Implement comprehensive unit and integration tests covering access control scenarios.
    • Follow secure coding practices to prevent authorization bypass vulnerabilities.
  • Users:
    • Carefully review and understand the privacy settings when creating and sharing memos.
    • Regularly review shared memos and their permissions to ensure they are configured as intended.
    • Report any unexpected behavior or unclear privacy settings to the developers.

Threat: Insecure Storage of Memos Data

• Description: If memo data is stored unencrypted or with weak encryption, an attacker who gains unauthorized access to the underlying storage (database, file system) could directly read and access all memo content. This could happen due to misconfiguration of the storage system, vulnerabilities in the hosting environment, or physical access to the server.
• Impact: Critical Confidentiality breach. Full disclosure of all memo content. This is a severe breach with potentially devastating consequences depending on the sensitivity of the stored information.
• Affected Component: Data Storage Layer (Database, File System), Encryption Module (if implemented).
• Risk Severity: Critical
• Mitigation Strategies:
  • Developers:
    • Implement strong encryption at rest for memo data. Use industry-standard encryption algorithms and best practices for key management.
    • Provide clear documentation and guidance on secure storage configuration for self-hosted instances.
    • Ensure the application supports and encourages secure database configurations (e.g., using TLS/SSL for database connections).
  • Users:
    • Ensure the database or file system used by Memos is properly secured and configured.
    • Enable encryption at rest for the database or storage volume if supported by the hosting environment.
    • Follow best practices for server security and access control to prevent unauthorized access to the storage layer.

Threat: Unauthorized Memo Modification or Deletion

• Description: An attacker, either an internal user with insufficient privileges or an external attacker who has bypassed authentication or authorization, could modify or delete memos they are not supposed to access. This could be due to flaws in permission checks, privilege escalation vulnerabilities, or session hijacking. An attacker might exploit API endpoints or direct database manipulation (if access is gained) to perform these actions.
• Impact: Integrity violation. Data loss or data corruption. Unauthorized modification can lead to misinformation, disruption of workflows, and loss of trust in the integrity of the memo system. Unauthorized deletion leads to data loss and potential disruption of operations.
• Affected Component: Access Control Module, Permission Management, API endpoints for memo modification and deletion.
• Risk Severity: High
• Mitigation Strategies:
  • Developers:
    • Implement robust and granular permission controls for memo modification and deletion, based on user roles and memo ownership/sharing.
    • Conduct thorough security audits and penetration testing of permission enforcement mechanisms.
    • Implement proper input validation and sanitization to prevent injection attacks that could bypass authorization.
  • Users:
    • Use strong passwords and practice good account security hygiene to prevent account compromise.
    • Regularly review user permissions and roles within the Memos application.

Threat: Privilege Escalation

• Description: An attacker with low-level privileges (e.g., a standard user) could exploit vulnerabilities in the application's access control or permission management to gain higher-level privileges (e.g., administrator). This could be due to flaws in role-based access control, insecure session management, or injection vulnerabilities. Once escalated, the attacker could perform actions reserved for administrators, such as accessing all memos, modifying user accounts, or changing system settings.
• Impact: Confidentiality, Integrity, and Availability impact. Full compromise of the Memos application. An attacker with administrator privileges can access all data, modify system settings, and potentially take over the entire application.
• Affected Component: Access Control Module, User Role Management, Session Management, Authentication and Authorization mechanisms.
• Risk Severity: Critical
• Mitigation Strategies:
  • Developers:
    • Implement a robust and well-defined role-based access control system.
    • Conduct thorough security audits and penetration testing focusing on privilege escalation vulnerabilities.
    • Follow secure coding practices to prevent authorization bypass and injection vulnerabilities.
    • Implement least privilege principles in application design.
  • Users:
    • Regularly review user accounts and their assigned roles to ensure appropriate privilege levels.
    • Use strong passwords and enable multi-factor authentication if available to protect administrator accounts.

Threat: Bypass of Access Control Checks

• Description: An attacker could exploit vulnerabilities in the application's code to bypass access control checks and gain unauthorized access to memos or functionalities. This could be due to flaws in authorization logic, insecure direct object references, or path traversal vulnerabilities. An attacker might manipulate API requests, URL parameters, or session tokens to circumvent access controls.
• Impact: Confidentiality, Integrity, and Availability impact depending on the bypassed access control. Unauthorized access to memos can lead to confidentiality breaches. Bypassing controls for modification or deletion can lead to integrity violations. Bypassing controls for critical functionalities can impact availability.
• Affected Component: Access Control Module, Authorization Logic, API endpoints, Routing and Request Handling.
• Risk Severity: High
• Mitigation Strategies:
  • Developers:
    • Implement secure and consistent access control checks at all relevant points in the application, especially in API endpoints and data access layers.
    • Avoid insecure direct object references and use indirect references or access control lists.
    • Conduct thorough security audits and penetration testing focusing on access control bypass vulnerabilities.
    • Follow secure coding practices and use security frameworks to enforce access control.
  • Users:
    • Report any observed behavior that suggests access control bypass vulnerabilities to the developers.

Threat: API Key or Token Leakage

• Description: If Memos uses API keys or tokens for authentication, leakage of these credentials could allow unauthorized access to the API and potentially to memo data. API keys or tokens could be leaked through various channels, such as client-side code, insecure storage, logging, or accidental disclosure.
• Impact: Confidentiality, Integrity, and Availability impact. Unauthorized access to the API can lead to data breaches, data manipulation, or denial of service depending on the permissions associated with the leaked API key or token.
• Affected Component: API Authentication Module, API Key/Token Management, Client-side code (if applicable), Logging.
• Risk Severity: High
• Mitigation Strategies:
  • Developers:
    • Avoid exposing API keys or tokens in client-side code if possible. Use secure server-side authentication mechanisms.
    • Implement secure storage and management of API keys and tokens.
    • Rotate API keys and tokens regularly.
    • Implement logging and monitoring for API key/token usage to detect potential leaks or unauthorized access.
  • Users:
    • Store API keys and tokens securely and avoid committing them to version control or sharing them insecurely.
    • Rotate API keys and tokens regularly.
    • Be cautious about where API keys and tokens are used and ensure they are not exposed in logs or insecure configurations.