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Mitigation Strategies Analysis for phpdocumentor/reflectioncommon

Mitigation Strategy: Strict Input Validation and Whitelisting (Reflection-Specific)

Description:

  1. Identify Reflection Input: Pinpoint all locations where data directly influences reflection operations using phpDocumentor/reflection-common. This includes any input used to construct class names, method names, property names, or type hints that are passed to reflection-common functions or classes.
  2. Define Reflection Whitelist: Create a strict, predefined list of allowed class names, method names, property names, and type hints that are permitted for reflection using reflection-common. This list should be as restrictive as possible.
  3. Implement Whitelist Check: Before any reflection-common call, verify that the input (class name, method name, etc.) is present in the whitelist. Use strict comparison (e.g., in_array()).
  4. Reject Non-Whitelisted Input: If the input is not in the whitelist, immediately reject the operation. Do not call any reflection-common functions. Throw an exception, log the attempt, and return a generic error.
  5. Format Validation (Reflection Context): Even for whitelisted input, perform format validation specifically tailored to the expected input type. Use regular expressions or other validation methods to ensure the input conforms to valid PHP syntax for class names, method names, etc., before passing it to reflection-common.

Threats Mitigated:

  • Code Injection (Indirect via Reflection): (Severity: Critical) - Prevents attackers from using reflection-common to instantiate arbitrary classes or trigger unexpected behavior by controlling class names, etc., passed to the library.
  • Information Disclosure (Reflection-Specific): (Severity: High) - Limits the scope of reflection performed by reflection-common to only authorized components, preventing leakage of internal details.
  • Denial of Service (Reflection-Induced): (Severity: Medium) - Reduces DoS risk by preventing reflection-common from being used to reflect on non-existent or excessively complex types, which could consume resources.

Impact:

  • Code Injection: Risk significantly reduced (nearly eliminated with a correct whitelist).
  • Information Disclosure: Risk significantly reduced, depending on whitelist comprehensiveness.
  • Denial of Service: Risk moderately reduced.

Currently Implemented:

  • Example: "No whitelisting is currently implemented for class names passed to ReflectionClass in the MetadataExtractor component."
  • Example: "Partial format validation exists for method names used with ReflectionMethod, but it's not comprehensive and doesn't use a whitelist."

Missing Implementation:

  • Example: "Whitelist for type hints used in DocBlockFactory::createInstance() is missing, allowing potentially malicious type hints to be processed."
  • Example: "Format validation for class names is missing before using FqsenResolver in the ConfigurationParser."

Mitigation Strategy: Contextual Access Control (Reflection-Specific)

Description:

  1. Identify reflection-common Usage: Locate all code points where phpDocumentor/reflection-common functions or classes are used.
  2. Define Access Rules: For each usage point, determine the necessary permissions or context (user roles, authentication, etc.) required to allow that specific reflection operation.
  3. Implement Pre-Reflection Checks: Before calling any reflection-common function, implement checks to verify that the current context meets the defined access requirements.
  4. Deny Unauthorized Reflection: If access is denied, prevent the reflection-common call. Throw an exception, log the attempt, and return a generic error.
  5. Blacklist Sensitive Components (Reflection Context): Create a list of classes, methods, properties, or type patterns that should never be reflected upon using reflection-common, regardless of user permissions. Block these explicitly.

Threats Mitigated:

  • Information Disclosure (Reflection-Specific): (Severity: High) - Prevents unauthorized access to sensitive information exposed through reflection-common, even with some input control.
  • Privilege Escalation (via Reflection): (Severity: High) - Prevents attackers from using reflection-common to bypass security and access restricted functionality.

Impact:

  • Information Disclosure: Risk significantly reduced, depending on access control granularity.
  • Privilege Escalation: Risk significantly reduced.

Currently Implemented:

  • Example: "No access control checks are performed before using reflection-common in the ApiDocGenerator."
  • Example: "Basic role-based checks exist before some reflection operations, but they are not consistently applied."

Missing Implementation:

  • Example: "Access control is missing before using DocBlockFactory to parse docblocks, potentially allowing unauthorized access to docblock information."
  • Example: "No blacklist of sensitive components exists to prevent reflection on internal classes using reflection-common."

Mitigation Strategy: Secure Error Handling (Reflection-Specific)

Description:

  1. Wrap reflection-common Calls: Enclose all calls to phpDocumentor/reflection-common functions and classes within try...catch blocks.
  2. Catch Reflection Exceptions: Specifically catch exceptions that can be thrown by reflection-common, such as those related to invalid types or parsing errors. Consult the reflection-common documentation for the specific exception types.
  3. Secure Error Handling (Reflection Context):
    • Never expose raw exception messages or stack traces from reflection-common to the user.
    • Log the error details securely, including the specific reflection-common function called, the input provided, and any relevant context.
    • Return a generic error message to the user.

Threats Mitigated:

  • Information Disclosure (via Error Messages): (Severity: Medium) - Prevents sensitive information from being leaked through error messages generated by reflection-common.

Impact:

  • Information Disclosure: Risk moderately reduced.

Currently Implemented:

  • Example: "Some try...catch blocks are present around reflection-common calls, but error messages are not always sanitized."
  • Example: "No specific exception handling for reflection-common errors is implemented in the TypeResolver component."

Missing Implementation:

  • Example: "Exceptions from DocBlockFactory::createInstance() are not caught, potentially exposing internal details to the user."
  • Example: "Error logging for reflection-common failures is inconsistent and doesn't always include sufficient context."