High advisory for The Forminator Forms – Contact Form

Advisory overview

The Forminator Forms – Contact Form, Payment Form & Custom Form Builder plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.57.3.1 via the 'previous_draft_id' parameter due to missing validation on a user controlled key. This makes it possible for unauthenticated attackers to delete arbitrary saved drafts belonging to other users and take over those draft identifiers by overwriting them with attacker-controlled form submissions. This requires the attacker to have obtained a victim's draft_id, which may be harvested from a shared "continue later" link; the nominally present nonce check is effectively bypassed because the nonce is publicly obtainable by any unauthenticated visitor loading a form page.

Related references

• https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/abstracts/abstract-class-front-action.php#L127
• https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/abstracts/abstract-class-front-action.php#L196
• https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/model/class-form-entry-model.php#L3110
• https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/model/class-form-entry-model.php#L429
• https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/modules/custom-forms/front/front-action.php#L1685
• https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/modules/custom-forms/front/front-action.php#L3662
• https://plugins.trac.wordpress.org/changeset/3732209/forminator/trunk/library/modules/custom-forms/front/front-action.php
• https://plugins.trac.wordpress.org/changeset?reponame=&new=3732192%40forminator%2Ftags%2F1.57.3.1&old=3700727%40forminator%2Ftags%2F1.57.3