mitigations.md

Mitigation Strategies Analysis for seldaek/monolog

Mitigation Strategy: Sensitive Data Masking/Sanitization (via Monolog Processors)

• Description:

  1. Identify Sensitive Data: Create a comprehensive list of all sensitive data types.
  2. Choose a Masking Approach: Select redaction, partial masking, hashing, or tokenization.
  3. Implement Monolog Processors: This is the core Monolog-specific step.
     • Custom Processor (Recommended): Create a PHP class implementing Monolog\Processor\ProcessorInterface. The __invoke method receives the log record ($record). Within this method:
       • Iterate through $record['context'].
       • Check keys against your sensitive data list.
       • Apply masking to matching values.
       • Modify $record['message'] using regex or string replacements (be very careful with regex).
       • Return the modified $record.
     • ReplaceProcessor (Less Flexible): Use Monolog\Processor\ReplaceProcessor with regex/replacement pairs for predictable patterns. Less robust than a custom processor.
     • PsrLogMessageProcessor (Supplementary): Use alongside a custom or ReplaceProcessor to handle placeholders in the message string.
  4. Register the Processor: Add the processor to your Monolog handler configuration in your application's logging setup.
  5. Testing: Create unit tests specifically for the masking processor, covering various sensitive data patterns and edge cases.

• Threats Mitigated:

  • Data Breach (Severity: Critical): Reduces exposure of sensitive data in compromised logs.
  • Compliance Violations (Severity: High): Helps meet data protection regulations.
  • Reputational Damage (Severity: High): Minimizes negative impact from data breaches.
  • Insider Threats (Severity: Medium): Reduces risk from malicious/negligent employees accessing logs.

• Impact:

  • Data Breach: Risk significantly reduced (effectiveness depends on implementation thoroughness).
  • Compliance Violations: Significantly reduces non-compliance risk.
  • Reputational Damage: Reduces likelihood and severity.
  • Insider Threats: Reduces risk, but doesn't eliminate it.

• Currently Implemented:

  • Example: Partially implemented. A basic ReplaceProcessor is used in src/Logging/LogManager.php.

• Missing Implementation:

  • No comprehensive custom processor.
  • No unit tests specifically for data masking.
  • No documented list of sensitive data types.

Mitigation Strategy: Log Injection Prevention (via Monolog Usage and Configuration)

• Description:

  1. Structured Logging: Always use the $context array in Monolog calls. Never embed user-supplied data directly into the message string.

     // BAD:
     $logger->info("User " . $userInput . " logged in.");
     
     // GOOD:
     $logger->info("User logged in.", ['username' => $userInput]);

  2. Message Size Limits (Handler Configuration): Configure the Monolog handler to limit the maximum size of log messages. This is often a handler-specific setting (e.g., RotatingFileHandler's options). This is a direct Monolog configuration.
  3. Escape special characters (within a custom Formatter, if necessary): If you absolutely must include potentially unsafe data, and you're using a custom formatter, escape special characters within the formatter's format method. This is a last resort and should be avoided if possible.

• Threats Mitigated:

  • Log Forging (Severity: Medium): Prevents injection of fake log entries.
  • Cross-Site Scripting (XSS) (Severity: High): Prevents XSS if logs are viewed in a web interface (requires proper output encoding in the viewer, but using context helps).
  • Command Injection (Severity: Critical): (Rare) Prevents command injection if logs are misused.
  • Denial of Service (DoS) (Severity: Medium): Prevents overwhelming the system with huge log entries.

• Impact:

  • Log Forging: Risk significantly reduced.
  • XSS: Risk reduced (relies on secure log viewing).
  • Command Injection: Risk significantly reduced.
  • DoS: Risk reduced (part of a broader DoS strategy).

• Currently Implemented:

  • The application mostly uses the $context array.

• Missing Implementation:

  • No specific message size limits are configured in Monolog handlers.
  • Some older code might embed user input directly (needs audit).

Mitigation Strategy: Handler-Specific Security Configuration (Direct Monolog Configuration)

• Description:

  1. Handler Inventory: List all Monolog handlers used.
  2. Security Review: For each handler:
     • Review Monolog's documentation for security options.
     • Identify potential risks.
     • Implement recommended security configurations directly within the handler's setup.
  3. Example: SwiftMailerHandler:
     • Ensure TLS/SSL is enabled in the handler's configuration.
     • Use strong authentication configured within the handler.
  4. Example: Network Handlers (SyslogUdpHandler, SocketHandler):
     • Use TLS/SSL if possible (configured in the handler).
  5. Avoid Risky Handlers: Avoid handlers sending logs to insecure destinations.

• Threats Mitigated:

  • Handler-Specific Vulnerabilities (Severity: Variable): Addresses vulnerabilities in specific handlers.
  • Data Interception (Severity: High): (For network handlers) Prevents interception in transit.
  • Unauthorized Access (Severity: High): (For network handlers) Prevents unauthorized access.

• Impact:

  • Handler-Specific Vulnerabilities: Risk reduced (depends on handler and configuration).
  • Data Interception: Risk significantly reduced with TLS/SSL.
  • Unauthorized Access: Risk significantly reduced.

• Currently Implemented:

  • The application uses StreamHandler, RotatingFileHandler, and SwiftMailerHandler.

• Missing Implementation:

  • Comprehensive review of all handler configurations hasn't been done.
  • TLS/SSL for SwiftMailerHandler needs verification and explicit configuration within the Monolog setup.

Mitigation Strategy: Least Privilege Principle with Formatter (Custom Monolog Formatter)

• Description:

  1. Identify Necessary Information: Determine the minimum information needed in logs.
  2. Choose/Create Formatter:
     • Customize LineFormatter: Use $format and $dateFormat to include only necessary fields. Remove unnecessary ones (e.g., full stack traces).
     • Custom Formatter (Recommended): Create a class implementing Monolog\Formatter\FormatterInterface. The format method receives the $record and returns a formatted string. This provides full control.
  3. Configure Handler: Assign the formatter to the Monolog handler in your application's logging configuration.

• Threats Mitigated:

  • Information Disclosure (Severity: Medium): Reduces information exposed in logs.
  • Data Breach (Severity: Critical): Reduces the impact of a breach.

• Impact:

  • Information Disclosure: Risk reduced.
  • Data Breach: Reduces scope and severity.

• Currently Implemented:

  • The application uses the default LineFormatter.

• Missing Implementation:

  • No custom formatters.
  • Default LineFormatter likely includes too much information. Needs review and customization.