threat-modeling.md

Threat Model Analysis for jetbrains/compose-multiplatform

Threat: Malicious Code Injection in Shared UI Logic

• Description: An attacker compromises the source code repository or a dependency and injects malicious code into a shared Compose UI component (e.g., a custom Composable function responsible for rendering a form or handling user input). The attacker could modify the component to subtly alter its behavior, such as redirecting a form submission to a malicious server or capturing user input without their knowledge. The key here is that the shared nature of the component propagates the attack across all target platforms.
  • Impact: Data theft (credentials, personal information), phishing, execution of arbitrary code on user devices, application compromise.
  • Component Affected: Shared Compose UI components (Composable functions, UI-related classes in the common module).
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Strict Code Reviews: Mandatory multi-person code reviews for all changes to shared UI components, with a focus on identifying potential injection points.
    • Dependency Management: Rigorous dependency audits, vulnerability scanning, and use of a Software Bill of Materials (SBOM) to track and vet all dependencies.
    • Input Validation: Rigorous input validation within the shared UI logic, specifically tailored to the expected data types and formats, to prevent injection attacks. This is in addition to any platform-specific validation.
    • Repository Access Control: Strong access controls on the source code repository (MFA, principle of least privilege, audit logs).

Threat: Tampering with Platform-Specific expect/actual Implementations

• Description: An attacker gains access to the source code and modifies the platform-specific implementation of an expect/actual declaration. This is a direct Compose Multiplatform threat because it exploits the mechanism for platform-specific code. For example, if there's an expect function for secure storage, the attacker could alter the Android actual implementation to store data insecurely, while leaving the iOS implementation untouched. This makes the attack harder to detect and leverages the cross-platform nature of the project.
  • Impact: Data leakage, privilege escalation, platform-specific compromise (potentially affecting only one platform, making it insidious).
  • Component Affected: Platform-specific modules containing actual implementations of expect declarations.
  • Risk Severity: High
  • Mitigation Strategies:
    • Separate Code Reviews: Treat expect/actual implementations as separate, high-risk components requiring independent code reviews, with reviewers possessing platform-specific security expertise.
    • Platform-Specific Security Expertise: Ensure reviewers have in-depth knowledge of the security best practices and common vulnerabilities for each target platform.
    • Automated Testing: Implement comprehensive automated tests that specifically target the actual implementations on each platform, including security-focused tests.
    • Runtime Checks: If feasible, add runtime checks within the actual implementations to verify expected behavior and detect anomalies (e.g., checking for unexpected file permissions or API return values).

Threat: Denial of Service via Shared Resource Exhaustion

• Description: An attacker crafts malicious input or exploits a logic flaw in a shared Compose component (e.g., a function that processes data or performs calculations) to cause excessive resource consumption (CPU, memory, network). The crucial point is that this flaw exists in the shared code, thus impacting all platforms simultaneously. An example is a recursive Compose function without proper termination, leading to a stack overflow on all platforms.
  • Impact: Application unavailability on all platforms, degraded user experience, potential data loss (if unsaved data is present).
  • Component Affected: Shared Compose components (functions, classes) in the common module that handle data processing, network requests, or complex calculations.
  • Risk Severity: High
  • Mitigation Strategies:
    • Input Validation: Thoroughly validate all input within the shared code to prevent excessively large or malformed data from being processed, focusing on inputs that could trigger resource-intensive operations.
    • Resource Limits: Implement resource limits (e.g., timeouts for network requests, memory allocation limits) within the shared code to prevent unbounded resource consumption.
    • Performance Testing: Conduct regular performance and stress testing, specifically targeting the shared components, to identify potential resource exhaustion vulnerabilities across all platforms.
    • Error Handling: Implement robust error handling in the shared code to gracefully handle unexpected conditions and prevent crashes due to resource exhaustion.
    • Asynchronous Operations: Use asynchronous operations (coroutines) strategically within the shared code to avoid blocking the main thread and maintain responsiveness, even under heavy load.

Threat: Dependency Vulnerabilities in Compose Multiplatform Libraries

• Description: A third-party library used by the Compose Multiplatform project (either a core Compose library or a community-maintained library specifically designed for Compose Multiplatform) contains a vulnerability. An attacker exploits this vulnerability to compromise the application. The direct involvement is that the vulnerability affects all platforms due to the shared nature of the Compose Multiplatform ecosystem.
  • Impact: Varies depending on the vulnerability, but could range from data leakage to remote code execution, and crucially, affects all platforms.
  • Component Affected: Any shared Compose component that uses the vulnerable library.
  • Risk Severity: High (depending on the vulnerability, but the cross-platform impact elevates the risk)
  • Mitigation Strategies:
    • Dependency Scanning: Use automated dependency scanning tools (e.g., Dependabot, Snyk, OWASP Dependency-Check) configured to specifically analyze the Compose Multiplatform project and its dependencies.
    • Regular Updates: Keep all dependencies, including Compose Multiplatform itself and third-party libraries, up-to-date, paying close attention to security releases.
    • Vulnerability Monitoring: Subscribe to security advisories and mailing lists for Compose Multiplatform and its dependencies, focusing on vulnerabilities that affect multiple platforms.
    • SBOM: Maintain a Software Bill of Materials (SBOM) to track all dependencies and their versions, enabling rapid identification of vulnerable components.

Threat: Insecure Data Transmission in Shared Network Logic (using Ktor or similar)

• Description: The shared Compose code handles network communication (e.g., making API requests using a multiplatform library like Ktor) but does not properly secure the data in transit. For example, it might use HTTP instead of HTTPS, or fail to validate server certificates within the shared Ktor client configuration. This affects all platforms using the shared networking logic.
  • Impact: Man-in-the-middle (MITM) attacks, data interception, data modification, affecting all platforms.
  • Component Affected: Shared Compose components that perform network communication (e.g., using Ktor or other multiplatform networking libraries) within the common module.
  • Risk Severity: High
  • Mitigation Strategies:
    • HTTPS Enforcement: Always use HTTPS for all network communication within the shared networking logic.
    • Certificate Pinning: Implement certificate pinning within the shared client configuration to prevent MITM attacks using forged certificates. This is crucial to do in the shared code, not just platform-specific configurations.
    • Secure Network Libraries: Use well-vetted and secure multiplatform networking libraries (e.g., Ktor) and ensure they are configured securely within the shared code.
    • Data Encryption: Encrypt sensitive data before transmitting it over the network, even if using HTTPS, within the shared logic. This adds an extra layer of protection.