threat-modeling.md

Threat Model Analysis for bpmn-io/bpmn-js

Threat: Cross-Site Scripting (XSS) via Malicious BPMN XML

• Description: An attacker crafts a malicious BPMN 2.0 XML diagram containing embedded JavaScript code within BPMN elements or attributes. When bpmn-js parses and renders this diagram, the malicious JavaScript executes in the user's browser.
  • Impact: Account compromise, data theft, malware distribution, defacement of the application.
  • Affected bpmn-js Component: bpmn-js core diagram rendering and XML parsing modules.
  • Risk Severity: High
  • Mitigation Strategies:
    • Server-Side BPMN XML Validation and Sanitization: Thoroughly validate and sanitize BPMN XML on the server-side before client-side rendering.
    • Content Security Policy (CSP): Implement a strict CSP to limit script sources and mitigate XSS execution.
    • Regular bpmn-js Updates: Keep bpmn-js updated to patch potential XSS vulnerabilities.

Threat: DOM-Based XSS through bpmn-js Vulnerabilities

• Description: A vulnerability within the bpmn-js library itself allows an attacker to inject malicious JavaScript into the application's DOM by exploiting flaws in bpmn-js rendering or event handling.
  • Impact: Account compromise, data theft, malware distribution, defacement of the application.
  • Affected bpmn-js Component: Potentially various modules within bpmn-js depending on the specific vulnerability, including rendering modules and event handling.
  • Risk Severity: High
  • Mitigation Strategies:
    • Regular bpmn-js Updates: Maintain up-to-date bpmn-js versions to patch library vulnerabilities.
    • Security Audits and Code Reviews: Conduct security reviews of application code integrating bpmn-js.
    • Input Validation (Application-Side): Validate user input interacting with bpmn-js.

Threat: Dependency Vulnerabilities in bpmn-js Dependencies

• Description: bpmn-js relies on third-party JavaScript dependencies. Vulnerabilities in these dependencies can be exploited through bpmn-js, potentially leading to XSS, remote code execution, or data breaches.
  • Impact: Potentially severe impacts depending on the dependency vulnerability, including XSS, data theft, or remote code execution.
  • Affected bpmn-js Component: Indirectly affects bpmn-js through its reliance on vulnerable dependencies.
  • Risk Severity: High (if dependency vulnerability is high or critical)
  • Mitigation Strategies:
    • Dependency Scanning and Management: Regularly scan bpmn-js dependencies for vulnerabilities.
    • Keep Dependencies Updated: Update bpmn-js and its dependencies to the latest versions.
    • Software Composition Analysis (SCA): Use SCA tools to monitor and manage dependency security.