Checkout Field Editor for WooCommerce < 1.8.0 - Admin+ PHP Object Injection

The plugin unserialize user input provided via the settings, which could allow high privilege users such as admin to perform PHP Object Injection when a suitable gadget is present

PoC

To simulate a gadget chain, put the following code in a plugin class Evil { public function __wakeup() : void { die(“Arbitrary deserialization”); } } Then import the following payload via WooCommerce > Checkout Form > Advanced Settings > Backup and Import Settings: Tzo0OiJFdmlsIjowOnt9Ow== Tzo0OiJFdmlsIjowOnt9Ow== being the base64 encode of serialized object: O:4:“Evil”:0:{};