Skip to content

Latest commit

 

History

History
123 lines (77 loc) · 14.1 KB

mitigations.md

File metadata and controls

123 lines (77 loc) · 14.1 KB

Mitigation Strategies Analysis for nwjs/nw.js

Mitigation Strategy: Principle of Least Privilege for File System Access (nw.js Context)

Description:

  1. Identify Required File Access in nw.js App: Developers must pinpoint the absolute minimum file system access needed for the nw.js application's features, considering its Node.js backend and web frontend interaction. Document these specific directories and file types.
  2. Restrict Access via Node.js APIs: In the Node.js backend of the nw.js application, use Node.js fs module functions and path manipulation (like path.join, path.resolve) to strictly control file paths. Avoid broad permissions and enforce access limitations programmatically within the Node.js code.
  3. Validate File Paths from Web Context: When the web frontend interacts with the Node.js backend for file operations, rigorously validate any file paths or filenames passed from the web context. Sanitize input to prevent path traversal attempts before Node.js code processes them.
  4. Prefer User-Initiated File Access in UI: Design the user interface to primarily rely on user-driven file selection using browser <input type="file"> elements or nw.js specific file dialogs (nw.FileDialog). This leverages user intent and reduces programmatic file path handling risks.
  5. Regularly Audit nw.js File Access Needs: Periodically review the application's file system access requirements within the nw.js context. Ensure that the implemented restrictions are still necessary and effective, removing any overly permissive access.

List of Threats Mitigated:

  • Path Traversal in nw.js Application (High Severity): Attackers exploiting nw.js's file access could bypass intended directory boundaries, accessing sensitive system files due to the Node.js backend's capabilities.
  • Arbitrary File Read via nw.js (High Severity): Unauthorized reading of local files becomes critical in nw.js due to the potential for Node.js to expose file system access to web vulnerabilities.
  • Arbitrary File Write via nw.js (High Severity): Malicious file modification or deletion through nw.js vulnerabilities can leverage Node.js's file system write capabilities, leading to significant damage.

Impact:

  • Path Traversal in nw.js Application: Significantly reduces risk by enforcing path boundaries within the nw.js application's Node.js backend.
  • Arbitrary File Read via nw.js: Significantly reduces risk by limiting the scope of readable files, even if web-based vulnerabilities are present in the nw.js application.
  • Arbitrary File Write via nw.js: Significantly reduces risk by restricting the writable file space, mitigating potential damage from compromised nw.js applications.

Currently Implemented: Partially implemented in the Node.js backend file processing, using path.join for path construction within nw.js.

Missing Implementation: Input validation for file paths passed from the web context to Node.js in the nw.js application is inconsistent. User-initiated file access is not fully prioritized in the UI of the nw.js application.

Mitigation Strategy: Minimize node-remote Usage and Control (nw.js Specific)

Description:

  1. Justify node-remote in nw.js: Strictly evaluate if node-remote is absolutely essential for the nw.js application. If remote content can function without Node.js privileges, avoid node-remote entirely.
  2. Whitelist node-remote URLs in nw.js Configuration: If node-remote is necessary, define a precise whitelist of allowed URLs or URL patterns within the nw.js application's configuration. Implement robust checks to ensure only whitelisted URLs are loaded in this privileged context.
  3. Sanitize URLs for node-remote Loading: Before loading any URL via node-remote in the nw.js application, rigorously sanitize and validate the URL to prevent URL manipulation or injection attacks that could bypass the whitelist.
  4. Apply Strict CSP to node-remote Content in nw.js: Even when using node-remote in nw.js, enforce a highly restrictive Content Security Policy (CSP) for the loaded remote content. This CSP should minimize script execution and resource loading capabilities within the Node.js context.
  5. Regularly Review node-remote Usage in nw.js: Periodically audit the nw.js application's usage of node-remote and the URL whitelist. Ensure the necessity of node-remote remains valid and the whitelist is up-to-date and secure.

List of Threats Mitigated:

  • Remote Code Execution (RCE) via node-remote in nw.js (Critical Severity): Loading malicious remote content in node-remote within nw.js grants immediate access to Node.js APIs and the local file system, enabling complete system compromise from within the nw.js application.
  • Cross-Site Scripting (XSS) Escalation in nw.js Node.js Context (High Severity): XSS vulnerabilities in remote content loaded via node-remote in nw.js become critically dangerous, allowing file system access and Node.js API exploitation directly from the compromised nw.js application.

Impact:

  • Remote Code Execution (RCE) via node-remote in nw.js: Significantly reduces risk by tightly controlling the sources of code that can execute with Node.js privileges within the nw.js application.
  • Cross-Site Scripting (XSS) Escalation in nw.js Node.js Context: Significantly reduces risk by limiting the capabilities of potentially compromised remote content loaded in nw.js, even if XSS vulnerabilities are present.

Currently Implemented: node-remote is used for specific external help documentation URLs in the nw.js application. A basic URL whitelist exists, checking against predefined domains.

Missing Implementation: The URL whitelist in the nw.js application is not dynamically updated and might miss legitimate URLs. URL sanitization for node-remote is basic and needs improvement. CSP is not applied to node-remote content within the nw.js application.

Mitigation Strategy: Disable Node.js Integration When Not Required (nodeIntegration: false in nw.js)

Description:

  1. Analyze Feature Dependencies in nw.js: Developers must meticulously analyze each feature of the nw.js application and determine if it truly requires Node.js APIs within the web context.
  2. Isolate Web Context in nw.js Windows: For parts of the nw.js application that do not need Node.js access, ensure they are loaded with nodeIntegration: false in the nw.js window configuration. This creates a secure boundary, isolating the web context from Node.js capabilities within the nw.js application.
  3. Architect for Separation in nw.js: Refactor the nw.js application's architecture to clearly separate functionalities that require Node.js from those that are purely web-based. This enables granular control over Node.js integration across different parts of the nw.js application.
  4. Default to nodeIntegration: false in nw.js: Adopt a principle of defaulting to nodeIntegration: false for all new windows or iframes within the nw.js application, unless Node.js integration is explicitly and demonstrably necessary.
  5. Regularly Review Integration Needs in nw.js: Periodically review the nw.js application's architecture and identify opportunities to further reduce or eliminate the need for nodeIntegration: true in the web context, minimizing the attack surface.

List of Threats Mitigated:

  • Exploitation of Web Context Vulnerabilities in nw.js (High Severity): If the web context of the nw.js application is compromised (e.g., via XSS), disabling Node.js integration prevents attackers from directly leveraging Node.js APIs and local file system access from within the web context.
  • Accidental Exposure of Node.js APIs in nw.js Web Context (Medium Severity): Reduces the risk of developers unintentionally using Node.js APIs in the web context of the nw.js application where they are not needed, potentially creating unforeseen vulnerabilities.

Impact:

  • Exploitation of Web Context Vulnerabilities in nw.js: Significantly reduces the impact of web context vulnerabilities within the nw.js application by limiting the attacker's capabilities, even if they gain control of the web context.
  • Accidental Exposure of Node.js APIs in nw.js Web Context: Reduces the likelihood of introducing vulnerabilities due to unintended or unnecessary Node.js API usage in the web context of the nw.js application.

Currently Implemented: The main application window and some UI components in the nw.js application are loaded with nodeIntegration: false.

Missing Implementation: Not consistently applied to all iframes or newly created windows within the nw.js application. A clear policy and guidelines for when to use nodeIntegration: true vs. false in the nw.js application are lacking.

Mitigation Strategy: Regular nw.js Updates (Framework Specific)

Description:

  1. Monitor nw.js Release Channels: Developers must actively monitor the official nw.js project's release channels (website, GitHub, etc.) specifically for new version announcements and security updates.
  2. Prioritize nw.js Security Updates: Treat nw.js updates, especially those explicitly marked as security releases, as critical and apply them with high priority to patch known vulnerabilities in the framework itself.
  3. Test nw.js Updates Thoroughly: Before deploying nw.js updates to production, rigorously test the new version in a staging environment to ensure compatibility with the application and identify any regressions introduced by the nw.js update.
  4. Automate nw.js Update Process (If Feasible): Explore and implement automation for the nw.js update process to streamline updates and ensure timely patching across the development lifecycle.
  5. Communicate nw.js Updates to Users: Inform users about application updates, highlighting security improvements from nw.js updates, encouraging them to use the latest, most secure version of the application.

List of Threats Mitigated:

  • Chromium Vulnerabilities in nw.js (High Severity): Outdated nw.js versions contain older Chromium versions, potentially exposing the application to known Chromium vulnerabilities that can lead to RCE and sandbox escapes within the nw.js application.
  • Node.js Vulnerabilities in nw.js (High Severity): Similarly, outdated nw.js versions may include vulnerable Node.js versions, exposing the application to Node.js-specific exploits that can be leveraged within the nw.js environment.

Impact:

  • Chromium Vulnerabilities in nw.js: Significantly reduces risk by patching known Chromium vulnerabilities within the nw.js framework, keeping the browser engine up-to-date with security best practices.
  • Node.js Vulnerabilities in nw.js: Significantly reduces risk by patching known Node.js vulnerabilities within the nw.js framework, benefiting from Node.js security improvements and reducing exposure to Node.js exploits.

Currently Implemented: Manual process of checking for nw.js updates and manually updating the application build.

Missing Implementation: Automated checks for nw.js updates and an automated update process are not implemented. No formal process for prioritizing and tracking nw.js security updates specifically.

Mitigation Strategy: Disable Developer Tools in Production (nw.js Configuration)

Description:

  1. Conditional devTools Configuration in nw.js: In the nw.js application's main script or window configuration, use conditional logic to enable developer tools only when running in a development or debugging environment.
  2. Set devTools: false for Production nw.js Builds: For production builds of the nw.js application, explicitly set the devTools: false option in the nw.js window configuration to disable access to developer tools in the final application.
  3. Integrate into nw.js Build Process: Integrate this devTools: false configuration into the application's build process for nw.js, ensuring that developer tools are automatically disabled in all production releases.
  4. Verify devTools Disabled in Production nw.js: After building the production nw.js application, rigorously verify that developer tools are indeed disabled by attempting to open them (typically by pressing F12 or right-clicking and selecting "Inspect") in the built application.

List of Threats Mitigated:

  • Information Disclosure via Developer Tools in nw.js (Medium Severity): Developer tools in a production nw.js application can expose sensitive application internals, source code, and potentially data to users, including malicious actors who could inspect the running nw.js application.
  • Client-Side Manipulation via Developer Tools in nw.js (Medium Severity): Attackers could use developer tools in a production nw.js application to modify the application's behavior at runtime, potentially bypassing security controls or injecting malicious code directly into the running nw.js application.

Impact:

  • Information Disclosure via Developer Tools in nw.js: Reduces risk by preventing easy access to the nw.js application's internals and code through readily available developer tools in production.
  • Client-Side Manipulation via Developer Tools in nw.js: Reduces risk by making it significantly harder for attackers to directly manipulate the nw.js application's runtime environment using built-in developer tools in a production setting.

Currently Implemented: Developer tools are generally enabled for development and debugging of the nw.js application.

Missing Implementation: Conditional logic to automatically disable developer tools in production builds of the nw.js application is not fully implemented in the build process. devTools: false is not consistently set for production releases of the nw.js application.