mitigations.md

Mitigation Strategies Analysis for jeremyevans/sequel

Mitigation Strategy: Always use Parameterized Queries

• Description:

  1. Identify all database queries: Review your application code and identify all places where database queries are constructed using Sequel.
  2. Replace string interpolation/concatenation with placeholders: Wherever user input is directly embedded into SQL queries using string interpolation (#{user_input}) or concatenation (+ user_input +), replace it with Sequel's placeholder mechanisms.
  3. Use :? or :$name placeholders: Utilize ? for positional placeholders or :$name for named placeholders in your query strings within Sequel's query builder methods.
  4. Pass user input as arguments to where, filter, prepare, or call methods: Provide user-supplied values as separate arguments to Sequel's query building methods. Sequel will handle proper escaping and parameterization.
  5. Test thoroughly: Test your application with various types of user input, including malicious strings, to ensure parameterized queries are correctly implemented and prevent SQL injection when using Sequel.

• List of Threats Mitigated:

  • SQL Injection (High Severity): Prevents attackers from injecting malicious SQL code into database queries constructed using Sequel, potentially leading to data breaches, data manipulation, or unauthorized access.

• Impact:

  • SQL Injection: Significantly reduces the risk of SQL injection vulnerabilities specifically when using Sequel to interact with the database.

• Currently Implemented:

  • To be determined. Needs to be checked across all database interaction points in the application that are using Sequel.

• Missing Implementation:

  • Potentially missing in older code sections, dynamically generated queries built with Sequel, or areas where developers might have bypassed Sequel's parameterization features. Needs code review to identify gaps in Sequel usage.

Mitigation Strategy: Avoid String Interpolation and Sequel.lit for User Input

• Description:

  1. Code Review for Interpolation/Sequel.lit in Sequel Queries: Conduct a thorough code review to identify instances where string interpolation (#{}) or Sequel.lit are used to incorporate user input directly into SQL queries constructed with Sequel.
  2. Replace with Parameterized Queries: For each identified instance, refactor the Sequel code to use parameterized queries as described in the "Always use Parameterized Queries" strategy, leveraging Sequel's built-in features.
  3. Establish Coding Standards for Sequel Usage: Implement coding standards and guidelines that explicitly prohibit the use of string interpolation and Sequel.lit for user-provided data when building SQL queries with Sequel.
  4. Use Static Analysis Tools: Consider using static analysis tools that can detect potential SQL injection vulnerabilities arising from string interpolation or misuse of Sequel.lit within Sequel code.

• List of Threats Mitigated:

  • SQL Injection (High Severity): Prevents injection vulnerabilities in Sequel applications that are directly caused by unsafe string manipulation in SQL queries built using Sequel features like Sequel.lit.

• Impact:

  • SQL Injection: Significantly reduces the risk of SQL injection by eliminating a common source of vulnerabilities within Sequel-based applications.

• Currently Implemented:

  • Partially implemented. Coding guidelines might mention this in relation to Sequel, but enforcement and consistent application need verification within Sequel code.

• Missing Implementation:

  • Potential inconsistencies across the codebase, especially in areas using Sequel. Older modules or less frequently updated sections using Sequel might still contain vulnerable patterns. Requires code audit focusing on Sequel usage and developer training on secure Sequel practices.

Mitigation Strategy: Use set_fields or Explicitly Define Allowed Attributes

• Description:

  1. Identify Model Update Points using Sequel Models: Locate all places in the application where Sequel model attributes are updated based on user input (e.g., from web forms, APIs) using Sequel's model functionality.
  2. Replace update or set with set_fields: Instead of using model.update(params) or model.set(params) directly with unfiltered user input in Sequel models, switch to using model.set_fields(params, :only => [:allowed_attributes]).
  3. Explicitly List Allowed Attributes in set_fields: In the :only option of set_fields within Sequel model updates, explicitly list the attributes that are permitted to be updated via mass assignment for each model and context.
  4. Review Allowed Attributes Regularly for Sequel Models: Periodically review the list of allowed attributes for each Sequel model to ensure it remains appropriate and doesn't inadvertently expose sensitive attributes to mass assignment through Sequel's set_fields functionality.

• List of Threats Mitigated:

  • Mass Assignment Vulnerability (Medium to High Severity): Prevents attackers from manipulating unintended Sequel model attributes by injecting unexpected parameters during mass assignment via Sequel's model update methods, potentially leading to unauthorized data modification, privilege escalation, or other security issues within the Sequel ORM context.

• Impact:

  • Mass Assignment Vulnerability: Significantly reduces the risk of mass assignment vulnerabilities specifically when using Sequel models for data manipulation.

• Currently Implemented:

  • To be determined. Developers might be using update or set directly with request parameters in Sequel models without explicit attribute filtering using set_fields.

• Missing Implementation:

  • Systematic use of set_fields with explicit :only lists across all Sequel model update operations based on user input.

Mitigation Strategy: Redact Sensitive Data in Logs

• Description:

  1. Identify Sensitive Data: Determine what data is considered sensitive in your application (e.g., passwords, API keys, personal identifiable information - PII, session tokens, credit card numbers) that might be logged by Sequel.
  2. Customize Sequel Logger: Extend or replace Sequel's default logger with a custom logger that implements redaction logic specifically for Sequel's query logging.
  3. Implement Redaction Rules for Sequel Logs: Define rules within the custom logger to identify and redact sensitive data from SQL queries logged by Sequel before they are written to the log output. This could involve:
     • Parameter Value Redaction: If using parameterized queries with Sequel, redact the values of parameters that are known to contain sensitive data (e.g., parameters named "password", "api_key") in Sequel logs.
     • Pattern-Based Redaction: Use regular expressions or pattern matching to identify and redact sensitive data within SQL query strings logged by Sequel.
     • Allow-listing/Block-listing: Maintain lists of sensitive keywords or table/column names relevant to Sequel queries to guide redaction in Sequel logs.
  4. Test Redaction Thoroughly for Sequel Logs: Test the redaction logic to ensure it effectively removes sensitive data from Sequel logs without inadvertently redacting non-sensitive information or breaking log analysis of Sequel queries.

• List of Threats Mitigated:

  • Information Disclosure via Logs (Medium to High Severity): Prevents sensitive data from being exposed in application logs generated by Sequel, which could be accessed by attackers if logs are compromised or improperly secured.

• Impact:

  • Information Disclosure: Significantly reduces the risk of information disclosure from Sequel logs by removing sensitive data.

• Currently Implemented:

  • Unlikely to be implemented. Default Sequel logging probably logs queries verbatim without redaction.

• Missing Implementation:

  • Custom Sequel logger with redaction logic. Configuration to use the custom logger instead of the default Sequel logger.

Mitigation Strategy: Customize Sequel's Error Handling

• Description:

  1. Explore Sequel's Error Handling Options: Review Sequel's documentation and explore its error handling features, such as custom error classes, error callbacks, and connection error handling specific to Sequel.
  2. Implement Custom Sequel Error Classes (Optional): Consider defining custom error classes that inherit from Sequel's error classes to provide more specific error handling logic and categorization for database errors encountered within Sequel operations.
  3. Use Sequel Error Callbacks (If Applicable): If appropriate, utilize Sequel's error callbacks to perform specific actions when database errors occur during Sequel operations (e.g., logging specific Sequel errors, implementing retry logic within Sequel).
  4. Customize Sequel Connection Error Handling: Implement robust connection error handling specifically for Sequel to gracefully manage database connection failures within Sequel and prevent application crashes or information leaks in case of connection issues related to Sequel's database interactions.

• List of Threats Mitigated:

  • Information Disclosure via Error Messages (Low to Medium Severity): Allows for finer-grained control over error handling within Sequel, potentially enabling more tailored error responses and reducing information disclosure from Sequel-related errors.
  • Application Availability and Resilience (Medium Severity): Improves application resilience by handling database errors gracefully within Sequel and preventing crashes or unexpected behavior arising from Sequel's database interactions.

• Impact:

  • Information Disclosure & Application Availability: Minimally to Moderately reduces the risk by providing more control over error handling behavior specifically within Sequel.

• Currently Implemented:

  • Unlikely to be implemented beyond basic exception handling. Customization of Sequel's error handling features is probably not a priority.

• Missing Implementation:

  • Exploration and utilization of Sequel's advanced error handling features. Custom Sequel error classes or callbacks. Tailored connection error handling within Sequel.