Description: An attacker might identify endpoints lacking server-side FluentValidation. They could then send malicious or malformed requests directly to these endpoints, bypassing client-side validation or targeting areas where validation is absent. This could involve crafting requests with invalid data types, exceeding length limits, or omitting required fields. Impact: Data corruption, application logic errors, unauthorized access to resources, potential for further exploitation of backend vulnerabilities due to processing invalid data. FluentValidation Component Affected: Validation Pipeline (or lack thereof) at specific endpoints. Risk Severity: High Mitigation Strategies: Implement FluentValidation on all server-side endpoints processing user input. Conduct regular security audits to identify and address any endpoints missing validation. Use automated testing to ensure validation is consistently applied across the application.
Threat: Ignoring Validation Results
Description: An attacker might exploit scenarios where developers implement FluentValidation but fail to check the IsValid result. By sending invalid data, they can force the application to process this data without proper validation, leading to unexpected behavior.
Impact: Data corruption, application logic errors, potential for crashes or unexpected application states, security vulnerabilities due to processing invalid data.
FluentValidation Component Affected: Validation Execution and Result Handling (Validator.Validate(), ValidationResult).
Risk Severity: High
Mitigation Strategies:
Always explicitly check the IsValid property of the ValidationResult after calling Validator.Validate().
Implement robust error handling to gracefully manage validation failures and prevent further processing of invalid data.
Use code analysis tools to detect instances where validation results are not properly checked.
Description: An attacker might exploit flaws in custom validators or complex validation logic that could lead to infinite loops or recursion during validation. This could be triggered by specific input values that cause the validation process to enter an endless loop, leading to a denial of service. Impact: Denial of Service (DoS), application crash, server resource exhaustion. FluentValidation Component Affected: Custom Validators, Complex Rule Chains, Recursive Validation Logic. Risk Severity: High Mitigation Strategies: Thoroughly test custom validators and complex validation logic with various inputs, including edge cases. Implement safeguards in custom validators to prevent infinite loops, such as setting iteration limits or timeouts. Use code reviews and static analysis tools to identify potential looping or recursion issues.
Description: An attacker could exploit known security vulnerabilities in the FluentValidation library itself or its dependencies. This could involve using publicly disclosed exploits or discovering new vulnerabilities to compromise the application. Impact: Full application compromise, data breach, denial of service, depending on the nature of the vulnerability. FluentValidation Component Affected: FluentValidation Library Core, Dependencies (e.g., .NET runtime). Risk Severity: Critical (if exploitable vulnerabilities exist) Mitigation Strategies: Keep FluentValidation and its dependencies up-to-date with the latest security patches. Regularly monitor security advisories and vulnerability databases for FluentValidation and its dependencies. Use dependency scanning tools to identify and manage known vulnerabilities in project dependencies. Implement a robust vulnerability management process.