The API does not properly validate, sanitize, or limit incoming data, accepting inputs that violate expected data types, ranges, formats, or sizes.
An attacker could inject malicious payloads, cause application errors, bypass business logic, trigger buffer overflows, or perform denial-of-service attacks through malformed input.
Implement strict input validation using allowlists and schema validation (e.g., JSON Schema, OpenAPI specification). Enforce data type, length, range, and format constraints. Sanitize inputs before processing. Return clear validation error messages.