CWE-1471 vulnerabilities

A vulnerability in the honojs hono web framework versions 4.5.1 through 4.13.15 allows unauthenticated clients to bypass form validation checks. The issue arises because the validator('form') method fails to recognize multipart/form-data Content-Type headers that include additional parameters or whitespace, causing the validation callback to receive an empty object. This can lead to bypassing allow-list or required-field checks if the application relies solely on this validator. The flaw is fixed in version 4.13.16.