CVE-2026-65049: Ninja Forms Cross-Site Network-Wide Data Deletion on WordPress Multisite via nf_delete_all_data AJAX Action

Ninja Forms plugin version 3.14.8 and prior for WordPress Multisite contains an incorrect authorization vulnerability that allows a subsite Administrator to trigger network-wide deletion of all Ninja Forms data by exploiting a site-scoped capability check combined with unsafe multisite migration defaults. Attackers can send a crafted POST request to the admin-ajax.php endpoint with the nfdeletealldata action and a per-site nonce to invoke migration routines that unconditionally iterate all blogs via switchtoblog(), dropping all nf3 tables and clearing options and transients across every subsite in the network without requiring super-admin or network-admin privileges.