mitigations.md

Mitigation Strategies Analysis for aspnet/entityframeworkcore

Mitigation Strategy: Parameterized Queries and Safe SQL Generation

Description:

1. Identify all Raw SQL: Search the codebase for all instances of FromSqlRaw and ExecuteSqlRaw. These are the primary areas of concern within EF Core.
2. Replace with Interpolated Versions: Replace FromSqlRaw with FromSqlInterpolated and ExecuteSqlRaw with ExecuteSqlInterpolated wherever possible. This allows using string interpolation in a safe, parameterized manner within EF Core's API.
3. Use SqlParameter Objects (If Interpolation Isn't Feasible): If string interpolation is not suitable (e.g., complex dynamic queries), use SqlParameter objects to explicitly define parameters. Pass these parameters to FromSqlRaw or ExecuteSqlRaw using EF Core's methods.
4. Review LINQ Queries: Examine LINQ queries for any manual string concatenation or building of query strings. Refactor these to use standard LINQ operators, letting EF Core's LINQ provider handle the SQL generation.
5. Code Reviews: Mandate code reviews that specifically check for proper parameterization and safe SQL generation practices within the context of EF Core usage.
6. Automated Scanning (Optional): Consider using static analysis tools that can detect potential SQL injection vulnerabilities, including those related to EF Core.

• Threats Mitigated:

  • SQL Injection: (Severity: Critical) Directly injecting malicious SQL code into the database through EF Core's methods.
  • Data Exposure: (Severity: High) Revealing sensitive data through error messages or unintended query results due to manipulated SQL executed via EF Core.

• Impact:

  • SQL Injection: Risk reduction: Very High. Parameterized queries using EF Core's mechanisms are the primary defense.
  • Data Exposure: Risk reduction: High. Preventing SQL injection through EF Core prevents associated data exposure.

• Currently Implemented: [ Placeholder: e.g., "Implemented in all API controllers. Verified through code reviews that FromSqlInterpolated is used consistently." ]

• Missing Implementation: [ Placeholder: e.g., "Not yet implemented in the legacy reporting module (ReportingService.cs). Needs refactoring to use FromSqlInterpolated." ]

Mitigation Strategy: View Models / DTOs (Data Transfer Objects)

Description:

1. Identify Entity Exposure: Locate all instances where EF Core entities are directly used in views (for MVC/Razor Pages) or returned from API controllers. This is about preventing direct interaction with the objects managed by EF Core.
2. Create View Models/DTOs: For each exposed EF Core entity, create a corresponding View Model or DTO. These classes should contain only the properties needed, and not expose the full entity managed by the context.
3. Mapping: Implement mapping logic between EF Core entities and View Models/DTOs.
4. Update Controllers/Views: Modify controllers and views to use the View Models/DTOs instead of the EF Core entities. This prevents direct binding to tracked objects.
5. Input Validation: Ensure View Models/DTOs have appropriate data annotations or validation logic.

• Threats Mitigated:

  • Over-Posting / Mass Assignment: (Severity: High) Attackers modifying properties they shouldn't have access to by submitting data that binds directly to EF Core's tracked entities.
  • Information Disclosure: (Severity: Medium) Unintentionally exposing sensitive data from EF Core entities in views or API responses.

• Impact:

  • Over-Posting / Mass Assignment: Risk reduction: Very High. Prevents direct modification of EF Core-managed objects.
  • Information Disclosure: Risk reduction: High. Limits exposure of entity properties.

• Currently Implemented: [ Placeholder: e.g., "Implemented for all new API endpoints." ]

• Missing Implementation: [ Placeholder: e.g., "Legacy MVC views still use entities directly." ]

Mitigation Strategy: Secure Error Handling (EF Core Configuration)

Description:

1. Disable Detailed Errors in Production (EF Core Setting): In your production configuration, ensure that EnableSensitiveDataLogging is set to false for your DbContext options within the EF Core configuration. This is a direct setting within EF Core.

   // In Startup.cs or Program.cs
   services.AddDbContext<MyDbContext>(options =>
   {
       options.UseSqlServer(Configuration.GetConnectionString("MyConnectionString"));
       #if !DEBUG
           options.EnableSensitiveDataLogging(false); // Disable in production - EF Core specific setting
       #endif
   });

2. Global Exception Handler: Implement a global exception handler.
3. Catch Specific EF Core Exceptions: Within the handler, catch EF Core exceptions like DbUpdateException.
4. Log Details Securely: Log the full exception details (securely).
5. User-Friendly Error Messages: Return generic error messages to the client.
6. Correlation IDs: Include a correlation ID.

• Threats Mitigated:

  • Sensitive Data Exposure in Error Messages (EF Core-Generated): (Severity: High) Revealing database schema details, SQL queries, or other sensitive information generated by EF Core in error messages.
  • Information Disclosure: (Severity: Medium) Providing attackers with clues through EF Core's error output.

• Impact:

  • Sensitive Data Exposure in Error Messages (EF Core-Generated): Risk reduction: Very High. The EnableSensitiveDataLogging(false) setting directly controls this.
  • Information Disclosure: Risk reduction: High.

• Currently Implemented: [ Placeholder: e.g., "EnableSensitiveDataLogging is set to false in appsettings.Production.json." ]

• Missing Implementation: [ Placeholder: e.g., "Need to review all catch blocks to ensure they are not exposing sensitive information." ]

Mitigation Strategy: Optimized Queries and Pagination (LINQ and EF Core Methods)

Description:

1. Identify Potential N+1 Problems (Using EF Core Profiling): Use EF Core's built-in logging or profiling tools to identify inefficient queries.
2. Use Eager Loading (EF Core Methods): Use .Include() and .ThenInclude() within your EF Core LINQ queries to eagerly load related data.
3. Projection (EF Core LINQ): Use .Select() in your LINQ queries to project only the necessary columns.
4. Avoid Client-Side Evaluation (LINQ Best Practices): Ensure that your LINQ queries can be fully translated to SQL by EF Core. Avoid premature use of AsEnumerable() or ToList().
5. Pagination (EF Core Methods): Use Skip() and Take() within your EF Core queries to implement pagination.
6. Query Timeouts (EF Core Configuration): Configure database query timeouts on the DbContext options using EF Core's configuration API.
7. Code Reviews: Include query performance and efficiency (specifically within LINQ to Entities) as part of code reviews.

• Threats Mitigated:

  • Denial of Service (DoS) via Inefficient Queries: (Severity: Medium) Attackers crafting requests that trigger slow queries handled by EF Core.
  • Performance Degradation: (Severity: Low to Medium) Slow queries generated by EF Core impacting responsiveness.

• Impact:

  • Denial of Service (DoS) via Inefficient Queries: Risk reduction: Medium to High. Optimized EF Core queries and pagination reduce the risk.
  • Performance Degradation: Risk reduction: High. Optimized LINQ to Entities queries improve performance.

• Currently Implemented: [ Placeholder: e.g., "Pagination implemented using Skip() and Take()." ]

• Missing Implementation: [ Placeholder: e.g., "Need to profile and optimize queries. Suspect N+1 problem." ]

Mitigation Strategy: AsNoTracking() for Read-Only Operations (EF Core Method)

Description:

1. Identify Read-Only Queries: Locate all queries where data is retrieved but not modified.
2. Apply AsNoTracking() (EF Core Method): Add .AsNoTracking() to these EF Core queries. This is a direct method call on the DbSet or IQueryable.

   var users = context.Users.AsNoTracking().Where(u => u.IsActive).ToList(); // EF Core method

3. Code Reviews: Enforce the use of AsNoTracking() during code reviews.

• Threats Mitigated:

  • Denial of Service (DoS) via Memory Exhaustion: (Severity: Low) Excessive memory usage due to EF Core tracking unnecessary entities.
  • Performance Degradation: (Severity: Low) Unnecessary EF Core tracking overhead.

• Impact:

  • Denial of Service (DoS) via Memory Exhaustion: Risk reduction: Low. AsNoTracking() reduces EF Core's memory footprint.
  • Performance Degradation: Risk reduction: Low to Medium. AsNoTracking() improves performance by avoiding EF Core's change tracking.

• Currently Implemented: [ Placeholder: e.g., "Implemented in most read-only API endpoints." ]

• Missing Implementation: [ Placeholder: e.g., "Need to review and update queries to use AsNoTracking()." ]

Mitigation Strategy: Secure Second-Level Caching (If Using EF Core-Compatible Provider)

Description:

1. Assess Necessity: Determine if second-level caching is truly required.
2. Choose Secure Provider: If using it, select a reputable caching provider that integrates with EF Core and has built-in security features.
3. Data Validation: Implement mechanisms to validate the integrity of cached data (this might involve interaction with the EF Core caching provider).
4. Short Expiration: Use short cache expiration times.
5. Cache Invalidation: Implement robust cache invalidation strategies integrated with EF Core's change tracking (if supported by the provider).
6. Configuration Review: Regularly review the caching provider's configuration (as it relates to EF Core integration).
7. Monitoring: Monitor cache access.

• Threats Mitigated:

  • Cache Poisoning: (Severity: Medium to High) Attackers manipulating data cached by EF Core's second-level cache.
  • Data Tampering: (Severity: Medium) Unauthorized modification of data in EF Core's cache.

• Impact:

  • Cache Poisoning: Risk reduction: High (if properly secured and integrated with EF Core).
  • Data Tampering: Risk reduction: Medium to High (if properly secured).

• Currently Implemented: [ Placeholder: e.g., "Second-level caching is not currently used." OR e.g., "Using a distributed cache provider with EF Core integration." ]

• Missing Implementation: [ Placeholder: e.g., "Need to implement data validation for cached entities." ]