threat-modeling.md

Threat Model Analysis for mozilla/addons-server

Threat: Malicious Addon Upload

• Description: An attacker uploads an addon containing malware by disguising it as legitimate. They exploit weaknesses in the upload validation process to get the malicious addon approved and distributed through addons-server.
• Impact: Users installing the malicious addon are compromised, leading to data theft, system compromise, and widespread harm. This severely damages the reputation and trust in the addon platform.
• Affected Component: Addon Upload Pipeline, Addon Validation Service, Code Review Processes
• Risk Severity: Critical
• Mitigation Strategies:
  • Implement robust multi-layered static and dynamic analysis of uploaded addon code.
  • Utilize sandboxing for addon analysis to prevent server compromise during analysis.
  • Mandatory code signing for all addons.
  • Establish strong community reporting and rapid takedown mechanisms.
  • Employ machine learning-based anomaly detection for addon behavior.

Threat: Server-Side Processing Vulnerabilities in Addon Analysis

• Description: A crafted malicious addon exploits vulnerabilities in addons-server's code during addon analysis (e.g., manifest parsing, static analysis). This could lead to Remote Code Execution (RCE) on the addons-server itself.
• Impact: Full compromise of the addons-server infrastructure, including data breaches, service disruption, and the ability to manipulate or distribute malicious addons at scale.
• Affected Component: Addon Analysis Service, Manifest Parser, Code Signing Module, Backend API
• Risk Severity: Critical
• Mitigation Strategies:
  • Adopt secure coding practices and rigorous code review for all addons-server components.
  • Regular security audits and penetration testing specifically targeting addon processing modules.
  • Isolate and sandbox addon analysis processes to limit the impact of potential vulnerabilities.
  • Implement strict input validation and sanitization for all data processed during addon analysis.

Threat: Compromised Addon Distribution

• Description: Attackers compromise the addons-server infrastructure or distribution channels to inject malicious addons or modified versions of legitimate addons into the distribution stream. This directly poisons the supply chain at the server level.
• Impact: Widespread distribution of malicious addons to a large user base, causing massive compromise and irreparable damage to user trust and platform reputation.
• Affected Component: Distribution Infrastructure (CDN, Mirrors), Backend API, Database, Infrastructure Security
• Risk Severity: Critical
• Mitigation Strategies:
  • Implement strong infrastructure security measures, including intrusion detection and prevention systems.
  • Secure the software supply chain for addons-server development and deployment.
  • Mandatory integrity checks and signing of addon packages before distribution.
  • Secure distribution channels with HTTPS and robust CDN security configurations.

Threat: Malicious Addon Updates

• Description: Attackers compromise legitimate developer accounts or gain unauthorized access to the update mechanism within addons-server to push malicious updates to existing addons.
• Impact: Existing users of previously safe addons are automatically updated to malicious versions, leading to widespread and silent compromise. This is particularly damaging as users trust existing addons.
• Affected Component: Update Mechanism, Developer Account Management, Backend API, Addon Version Control
• Risk Severity: Critical
• Mitigation Strategies:
  • Enforce mandatory Multi-Factor Authentication (MFA) for all developer accounts.
  • Implement secure and auditable update mechanisms with version control and rollback capabilities.
  • Require code signing for all addon updates and verify signatures.
  • Implement update review processes, especially for significant updates or updates from less active developers.

Threat: Admin Interface Exposure and Vulnerabilities

• Description: Vulnerabilities in the addons-server administrative interface or its misconfiguration allow unauthorized access to administrative functions.
• Impact: Complete compromise of the addons-server system, allowing attackers to control all aspects of the platform, including addon management, user data, and potentially the underlying infrastructure.
• Affected Component: Admin Interface, Authentication System, Backend API, Infrastructure Security
• Risk Severity: Critical
• Mitigation Strategies:
  • Secure admin interface access with strong MFA and IP whitelisting.
  • Regular security audits and penetration testing of the admin interface.
  • Principle of least privilege for admin accounts, limiting access to only necessary functions.
  • Keep admin interface software and dependencies up-to-date with security patches.

Threat: Vulnerable Addon Upload

• Description: Developers unintentionally upload addons containing security vulnerabilities (e.g., XSS, CSRF, insecure API calls). addons-server distributes these vulnerable addons, making users susceptible to exploitation.
• Impact: Users of vulnerable addons are exposed to attacks like cross-site scripting, data breaches within the addon context, and potential browser-based exploits.
• Affected Component: Addon Upload Pipeline, Addon Validation Service (limited detection of runtime vulnerabilities), User Browser Environment
• Risk Severity: High
• Mitigation Strategies:
  • Provide comprehensive developer education and resources on secure addon development.
  • Integrate automated Static Application Security Testing (SAST) tools into the addon upload process to detect common vulnerabilities.
  • Encourage developers to use security linters and static analysis tools during development.
  • Establish a clear vulnerability disclosure program for addons and a process for rapid patching and updates.

Threat: Bypass of Addon Validation Checks

• Description: Attackers discover and exploit weaknesses or loopholes in the addons-server's addon validation and scanning processes to upload malicious addons undetected.
• Impact: Malicious addons bypass security measures and are distributed to users, undermining the platform's security and exposing users to harm.
• Affected Component: Addon Validation Service, Validation Rules Engine, Security Monitoring
• Risk Severity: High
• Mitigation Strategies:
  • Continuously improve and evolve validation processes based on emerging threats and attacker techniques.
  • Implement layered security checks and defense-in-depth within the validation pipeline.
  • Proactive threat hunting and monitoring for bypass attempts and suspicious upload patterns.
  • Regularly review and update validation rules, signatures, and detection mechanisms.

Threat: Authorization Bypass in API Access

• Description: Vulnerabilities in the addons-server's API authorization logic allow attackers to bypass access controls and perform unauthorized actions, such as modifying addon metadata or accessing developer resources.
• Impact: Unauthorized access to sensitive data and functionalities, potential data breaches, manipulation of addon information, and potential escalation of privileges.
• Affected Component: API Gateway, Authorization Module, Backend APIs, Access Control Lists
• Risk Severity: High
• Mitigation Strategies:
  • Implement robust and well-tested authorization mechanisms (e.g., OAuth 2.0, JWT) for all APIs.
  • Adhere strictly to the principle of least privilege in API access control.
  • Regular security audits and penetration testing of API authorization logic and endpoints.
  • Implement comprehensive logging and monitoring of API access and authorization events.

Threat: Developer Account Compromise

• Description: Developer accounts are compromised through phishing, credential stuffing, or other account takeover methods. Attackers then use these compromised accounts to upload malicious addons or updates.
• Impact: Attackers can distribute malicious addons or updates under the guise of legitimate developers, eroding user trust and potentially causing widespread harm.
• Affected Component: Developer Account Management, Authentication System, Backend API
• Risk Severity: High
• Mitigation Strategies:
  • Enforce strong password policies and complexity requirements for developer accounts.
  • Mandatory Multi-Factor Authentication (MFA) for all developer accounts.
  • Implement account lockout policies and rate limiting for login attempts.
  • Proactive monitoring for suspicious account activity and login patterns.
  • Developer education and awareness training on account security and phishing prevention.

Threat: Data Breaches and Data Leakage due to addons-server Vulnerabilities

• Description: Vulnerabilities within the addons-server application itself (e.g., SQL injection, insecure API endpoints, access control flaws) lead to the exposure of sensitive data stored by the server (developer information, addon metadata, usage statistics).
• Impact: Privacy violations, reputational damage, legal liabilities, and potential misuse of leaked data, including developer credentials or addon-related sensitive information.
• Affected Component: Database, Data Storage, Backend APIs, Logging Systems
• Risk Severity: High
• Mitigation Strategies:
  • Secure coding practices to prevent common web application vulnerabilities (e.g., input validation, output encoding, parameterized queries).
  • Regular security audits and vulnerability assessments of addons-server code and infrastructure.
  • Data minimization - only store necessary sensitive data.
  • Encryption of sensitive data at rest and in transit.
  • Strict access control to databases and sensitive data stores.