CVE-2026-89435

The Formidable Forms – WordPress Form Builder for Contact Forms, Calculators, Quizzes & More plugin for WordPress is vulnerable to Arbitrary Plugin Installation in all versions up to, and including, 6.35 via the 'file url' parameter parameter. This is due to insufficient URL prefix validation in validate url is in s3 bucket() and a permission callback that relies solely on a shared token obtainable by any user with the delegable frm view forms capability, without checking install plugins or activate plugins capabilities. This makes it possible for authenticated attackers, with subscriber-level access and above, to install arbitrary plugins on the server. Exploitation additionally requires that the site is free-only (Formidable Pro is NOT installed).