mitigations.md

Mitigation Strategies Analysis for facebookincubator/socketrocket

Mitigation Strategy: Enforce WSS (WebSocket Secure)

Mitigation Strategy: Enforce WSS (WebSocket Secure)

Here's a refined list of mitigation strategies that directly involve the SocketRocket library, focusing on its configuration and usage to enhance security.

Mitigation Strategy: Enforce WSS (WebSocket Secure)

• Description:

  1. Code Review: Inspect all instances where SRWebSocket is initialized.
  2. URL Verification: Ensure that the WebSocket URL passed to SRWebSocket constructor always starts with wss:// instead of ws://.
  3. Configuration Enforcement: If using configuration files or environment variables for WebSocket URLs, strictly enforce that only wss:// URLs are permitted for SRWebSocket initialization.
  4. Testing: Conduct integration tests to verify that SRWebSocket connections are established using WSS and that data is encrypted during transmission.

• Threats Mitigated:

  • Eavesdropping (High Severity): Unencrypted ws:// connections transmit data in plaintext, allowing attackers to intercept and read sensitive information communicated via SRWebSocket.
  • Man-in-the-Middle Attacks (High Severity): Without encryption, attackers can intercept and modify communication between the client and server using SRWebSocket, potentially injecting malicious data or stealing credentials.

• Impact:

  • Eavesdropping: High reduction - WSS encryption, enforced through SRWebSocket, makes eavesdropping extremely difficult.
  • Man-in-the-Middle Attacks: High reduction - WSS, when used with SRWebSocket, provides authentication and encryption, significantly hindering man-in-the-middle attacks.

• Currently Implemented:

  • Implemented in the application's network layer where SRWebSocket connections are established. URLs are configured to use wss:// in production environments for SRWebSocket.

• Missing Implementation:

  • No missing implementation currently for production SRWebSocket usage. However, ensure development and testing environments also default to wss:// or have clear documentation to avoid accidental ws:// usage in production with SRWebSocket.

Mitigation Strategy: Implement Certificate Pinning

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Mitigation Strategy: Implement Certificate Pinning

• Description:

  1. Certificate/Public Key Extraction: Obtain the server's TLS/SSL certificate or its public key used for WSS connections with SRWebSocket.
  2. Pinning Implementation within SRWebSocketDelegate: Integrate certificate pinning within the application's network layer, specifically using the SRWebSocketDelegate methods. This involves:
     • Bundling the server's certificate or public key within the application.
     • Implementing custom certificate validation in SRWebSocketDelegate methods like webSocket:didReceiveAuthenticationChallenge:.
     • Comparing the server's presented certificate against the pinned certificate or public key within the delegate.
     • Rejecting the SRWebSocket connection in the delegate if the certificate does not match the pinned value.
  3. Pin Rotation Strategy: Establish a process for rotating pinned certificates or public keys used by SRWebSocket when server certificates are updated. This might involve application updates or remote configuration updates.
  4. Testing: Thoroughly test the pinning implementation for SRWebSocket by attempting connections with valid and invalid certificates (e.g., using a self-signed certificate or a certificate from a different domain) and verifying the delegate's behavior.

• Threats Mitigated:

  • Man-in-the-Middle Attacks via Compromised CAs (High Severity): If a Certificate Authority (CA) is compromised, attackers could issue fraudulent certificates for your domain. Certificate pinning within SRWebSocketDelegate prevents reliance solely on CAs and mitigates this risk for WebSocket connections.

• Impact:

  • Man-in-the-Middle Attacks via Compromised CAs: High reduction - Pinning within SRWebSocketDelegate ensures that even if a CA is compromised, SRWebSocket connections to your server are still protected as only the pinned certificate is trusted.

• Currently Implemented:

  • Not currently implemented for SRWebSocket. Standard system certificate validation is used for SRWebSocket connections.

• Missing Implementation:

  • Certificate pinning is missing in the network layer for SRWebSocket connections. Implementation is needed within the SRWebSocketDelegate methods, specifically webSocket:didReceiveAuthenticationChallenge:, to perform custom certificate validation.

Mitigation Strategy: Implement Message Size Limits

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Mitigation Strategy: Implement Message Size Limits

• Description:

  1. SocketRocket Configuration (if available): Explore SRWebSocket configuration options to set a maximum allowed message size directly within the library's settings. If direct configuration is limited, consider implementing size checks within the SRWebSocketDelegate.
  2. Delegate-Based Size Checks: If direct configuration is insufficient, implement message size checks within the SRWebSocketDelegate method webSocket:didReceiveMessage:. Before processing the message, check its size against a defined limit.
  3. Define Reasonable Limits: Determine appropriate message size limits for SRWebSocket based on the application's expected data volume and resource constraints. Consider both incoming and outgoing message sizes handled by SRWebSocket.
  4. Error Handling in Delegate: Implement error handling in SRWebSocketDelegate methods to gracefully handle situations where messages exceed the configured size limit. Log errors and potentially close the SRWebSocket connection if necessary.

• Threats Mitigated:

  • Denial of Service (DoS) via Large Messages (Medium to High Severity): Attackers can send excessively large WebSocket messages through SRWebSocket to consume server and client resources (memory, bandwidth, processing power), potentially leading to denial of service.

• Impact:

  • Denial of Service (DoS) via Large Messages: Medium to High reduction - Limiting message sizes for SRWebSocket prevents attackers from easily overwhelming the application with oversized messages sent via WebSocket. The impact depends on how effectively the limits are enforced within SRWebSocket usage and the application's resource capacity.

• Currently Implemented:

  • No explicit message size limits are currently configured for SRWebSocket usage.

• Missing Implementation:

  • Message size limits need to be implemented for SRWebSocket. Explore direct configuration options first. If not sufficient, implement size checks within the SRWebSocketDelegate method webSocket:didReceiveMessage:. Reasonable limits should be determined based on application requirements and resource constraints for SRWebSocket communication.

Mitigation Strategy: Handle Unexpected/Malformed Messages Gracefully

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Mitigation Strategy: Handle Unexpected/Malformed Messages Gracefully

• Description:
  1. Error Handling in SRWebSocketDelegate Methods: Implement comprehensive error handling within SRWebSocketDelegate methods, particularly in webSocket:didReceiveMessage: which processes incoming messages from SRWebSocket.
  2. Exception Handling within Delegate: Use try-catch blocks or similar mechanisms within SRWebSocketDelegate methods to handle potential exceptions during message processing (e.g., JSON parsing errors, data validation errors) of messages received via SRWebSocket.
  3. Logging within Delegate: Log errors and details about unexpected or malformed messages received by SRWebSocket within the SRWebSocketDelegate methods for debugging and security monitoring purposes. Include relevant information like message content (if safe to log), error type, and timestamp.
  4. Graceful Degradation based on SRWebSocket state: Design the application to gracefully handle situations where message processing from SRWebSocket fails. Avoid crashing or exposing sensitive information. Handle errors within the SRWebSocketDelegate and consider strategies like:
     • Ignoring the malformed message from SRWebSocket and continuing operation.
     • Requesting re-transmission of the message via SRWebSocket (if applicable protocol).