Mitigation Strategy: Rigorous Code Reviews with Multiplatform Checklist
Mitigation Strategy: Rigorous Code Reviews with Multiplatform Checklist
* **Description:**
1. **Establish a Checklist:** Create a code review checklist *specifically* for Compose Multiplatform projects. This is crucial because shared code impacts all platforms. The checklist *must* include:
* **`expect`/`actual` Contract Adherence:** Verify that `actual` implementations strictly adhere to the contract defined by the `expect` declaration. Check for type mismatches, unexpected behavior, and potential security vulnerabilities.
* **Platform-Specific API Misuse in `actual`:** Review each `actual` implementation for incorrect or insecure use of platform-specific APIs. This requires reviewers with platform-specific expertise.
* **`commonMain` Dependency Review:** Scrutinize all dependencies added to `commonMain`. A vulnerable dependency here affects *all* target platforms.
* **UI State Management (Cross-Platform):** Assess how UI state is managed and shared across platforms. Ensure sensitive data is not inadvertently exposed or leaked due to platform-specific differences.
* **Input Sanitization (Composable Level):** Verify that all user inputs within Composables are properly sanitized *before* being used to update the UI state or trigger actions. This is crucial even if platform-level input handling exists.
2. **Mandatory Reviews (commonMain & actual):** Make code reviews absolutely mandatory for *all* changes to `commonMain` and *all* `actual` implementations. No exceptions.
3. **Cross-Functional Reviewers:** *Require* reviewers with expertise in *different* target platforms (Android, iOS, Desktop, Web) to participate in reviews. This is essential to catch platform-specific nuances and potential vulnerabilities.
4. **`commonMain` Focus:** Apply *extra* scrutiny to code in `commonMain`, as vulnerabilities here have amplified impact.
5. **Document Findings:** Thoroughly document all findings, discussions, and resolutions. This creates an audit trail and helps with future reviews.
6. **Regular Checklist Updates:** Regularly review and update the checklist to address new Compose Multiplatform features, threats, and best practices.
* **Threats Mitigated:**
* **Cross-Platform Code Vulnerability Propagation (High Severity):** The primary threat mitigated. A single vulnerability in `commonMain` can affect all platforms.
* **Platform-Specific API Misuse (Medium to High Severity):** Incorrect or insecure use of platform APIs in `actual` implementations can lead to platform-specific vulnerabilities.
* **UI-Specific Vulnerabilities (Medium Severity):** Improper input handling or state management within Composables can create vulnerabilities, especially when combined with platform-specific differences.
* **Impact:**
* **Cross-Platform Vulnerability Propagation:** Reduces risk by 70-80%.
* **Platform-Specific API Misuse:** Reduces risk by 60-70%.
* **UI-Specific Vulnerabilities:** Reduces risk by 50-60%.
* **Currently Implemented:**
* Mandatory code reviews are in place.
* A general Kotlin checklist is used.
* **Missing Implementation:**
* A *dedicated* Compose Multiplatform checklist is missing.
* Cross-functional reviewers are not consistently involved.
* Documentation of findings is inconsistent.
Mitigation Strategy: Multiplatform-Aware Static Analysis
Mitigation Strategy: Multiplatform-Aware Static Analysis
* **Description:**
1. **Tool Selection:** Choose static analysis tools that *explicitly* support Kotlin Multiplatform *and* Compose Multiplatform. Standard Kotlin linters are *insufficient*. Look for tools that can analyze the generated platform-specific code.
2. **Configuration (All Source Sets):** Configure the tools to analyze *all* source sets (`commonMain`, `androidMain`, `iosMain`, `jvmMain`, `jsMain`, etc.). This is crucial to catch platform-specific issues.
3. **Custom Rules (Multiplatform-Specific):** Develop custom rules for the static analysis tools to address security concerns *unique* to Compose Multiplatform. Examples:
* Insecure use of `expect`/`actual` (e.g., type mismatches, permission issues).
* Potential data leaks in UI state due to platform-specific behavior.
* Improper handling of platform-specific APIs within `actual` implementations.
* Vulnerabilities in third-party Compose Multiplatform libraries.
4. **CI/CD Integration:** Integrate the static analysis tools into the CI/CD pipeline. Run the analysis automatically on every commit and build.
5. **False Positive Management:** Establish a process for reviewing and managing false positives.
6. **Regular Updates:** Keep the tools and custom rules updated.
* **Threats Mitigated:**
* **Cross-Platform Code Vulnerability Propagation (High Severity):** Detects vulnerabilities in shared code (`commonMain`) that affect all platforms.
* **Platform-Specific API Misuse (Medium to High Severity):** Identifies insecure use of platform APIs in `actual` implementations.
* **UI-Specific Vulnerabilities (Medium Severity):** Catches potential issues in Compose UI code that might manifest differently across platforms.
* **Impact:**
* **Cross-Platform Vulnerability Propagation:** Reduces risk by 50-60%.
* **Platform-Specific API Misuse:** Reduces risk by 40-50%.
* **UI-Specific Vulnerabilities:** Reduces risk by 30-40%.
* **Currently Implemented:**
* A basic Kotlin linter (Detekt) is in the CI/CD pipeline.
* **Missing Implementation:**
* The current linter is *not* configured for Kotlin Multiplatform or Compose Multiplatform.
* No custom rules for multiplatform-specific concerns.
* Analysis is limited to `commonMain` (not all source sets).
Mitigation Strategy: Platform-Specific Integration and UI Testing
Mitigation Strategy: Platform-Specific Integration and UI Testing
* **Description:**
1. **Separate Test Suites:** Create *separate* integration and UI test suites for *each* target platform (Android, iOS, Desktop, Web). This is essential because the same Compose code can behave differently on each platform.
2. **Focus on Platform Interactions:** Design tests that specifically exercise the interactions between the shared Compose UI code and the underlying platform APIs. This is where platform-specific vulnerabilities are most likely to arise.
3. **Input Validation (Platform-Specific):** Include tests that provide various inputs (valid, invalid, edge cases) to UI components and verify the expected behavior on *each* platform. Platform-specific input handling differences can lead to vulnerabilities.
4. **Deep Link/URI Handling (Platform-Specific):** If the app handles deep links or custom URIs, create tests that simulate these on *each* platform, including malicious or malformed inputs. This is a common attack vector, especially on Android and iOS.
5. **UI State Verification (Cross-Platform):** Verify that the UI state is updated correctly and that sensitive data is not unintentionally exposed on *any* platform.
6. **Automated Execution (CI/CD):** Integrate these tests into the CI/CD pipeline for automated execution on every build.
7. **Real Devices/Emulators/Simulators:** Run tests on a variety of real devices, emulators, and simulators to cover different configurations.
* **Threats Mitigated:**
* **Platform-Specific API Misuse (Medium to High Severity):** Catches issues arising from incorrect interactions with platform APIs, which are only detectable on the specific platform.
* **UI-Specific Vulnerabilities (Medium Severity):** Identifies platform-specific rendering or behavior issues in the Compose UI that are not apparent in unit tests.
* **Deep Linking/URI Handling Vulnerabilities (High Severity):** Detects vulnerabilities related to deep link and URI handling, which are highly platform-specific.
* **Impact:**
* **Platform-Specific API Misuse:** Reduces risk by 60-70%.
* **UI-Specific Vulnerabilities:** Reduces risk by 50-60%.
* **Deep Linking/URI Handling Vulnerabilities:** Reduces risk by 70-80%.
* **Currently Implemented:**
* Basic unit tests for `commonMain`.
* Limited UI tests for Android.
* **Missing Implementation:**
* No integration tests for any platform.
* UI tests are missing for iOS, Desktop, and Web.
* Existing tests don't comprehensively cover platform interactions or deep links.
* Tests are not consistently run on diverse devices/emulators.
Mitigation Strategy: Secure expect/actual Implementation
Mitigation Strategy: Secure expect/actual Implementation
* **Description:**
1. **Restrictive `expect` Contracts:** Define `expect` declarations with the *most restrictive* possible contracts. Minimize the surface area exposed to `actual` implementations. Be extremely precise about input/output types and expected behavior.
2. **Least Privilege in `actual`:** Implement `actual` declarations with the principle of least privilege. Grant *only* the necessary permissions and access to platform resources. Avoid overly broad permissions.
3. **Input Validation in `actual`:** Even with a strict `expect` contract, perform additional input validation *within* the `actual` implementation. This is a defense-in-depth measure.
4. **Secure API Usage:** Use platform-specific security APIs *correctly* within `actual` implementations (e.g., Keychain on iOS, Keystore on Android for sensitive data).
5. **Defensive Programming:** Write defensive code in *both* `expect` and `actual` implementations. Handle potential errors and exceptions gracefully. Assume the other side might not behave as expected.
6. **Separate Security Audits:** Conduct *separate* security audits for *each* `actual` implementation. Treat each as an independent security boundary.
* **Threats Mitigated:**
* **Platform-Specific API Misuse (Medium to High Severity):** The primary threat. Prevents insecure use of platform APIs, which is the core purpose of `expect`/`actual`.
* **Privilege Escalation (High Severity):** Reduces the risk of an attacker gaining elevated privileges through a vulnerable `actual` implementation.
* **Data Leakage (High Severity):** Protects against data leakage through insecure handling of sensitive data in `actual` implementations.
* **Impact:**
* **Platform-Specific API Misuse:** Reduces risk by 70-80%.
* **Privilege Escalation:** Reduces risk by 80-90%.
* **Data Leakage:** Reduces risk by 70-80%.
* **Currently Implemented:**
* Basic `expect`/`actual` implementations exist.
* **Missing Implementation:**
* `expect` declarations are not always maximally restrictive.
* Least privilege is not consistently applied in `actual`.
* Input validation is not always present in `actual`.
* Separate security audits for each `actual` are not performed.