CVE-2026-71434: Statamic: Missing file upload validation on frontend forms allows uploading disallowed file types

Public frontend forms did not enforce the file upload restrictions that the Control Panel enforces, so an unauthenticated visitor could upload file types an administrator had intended to disallow through a form’s assets or files field. For assets fields, files could be stored on a public, web-accessible disk. Statamic’s global upload allowlist still applied, so executable types such as .php and .html remained blocked.