# Back In Stock Notifier for WooCommerce | WooCommerce Waitlist Pro <= 7.4.5 - Authenticated (Author+) Insecure Direct Object Reference to Arbitrary Post Modification via REST API update_subscriber 'ID' Parameter

- **ID:** WPSEC-2026-1117
- **Plugin:** Back In Stock Notifier for WooCommerce | WooCommerce Waitlist Pro (`back-in-stock-notifier-for-woocommerce`), https://wordpress.org/plugins/back-in-stock-notifier-for-woocommerce/
- **Affected versions:** all versions before 7.5.0
- **Fixed in:** 7.5.0 (Update to 7.5.0 or later.)
- **Severity:** Medium 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N)
- **Weakness:** CWE-639
- **Usage among sites WPSec scans:** plugin Medium, affected versions Medium (as of 2026-10-16)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/back-in-stock-notifier-for-woocommerce
- **Fix released:** 2026-10-15
- **Published:** 2026-10-16
- **URL:** https://wpsec.com/vuln/WPSEC-2026-1117/

## Description

The Back In Stock Notifier for WooCommerce | WooCommerce Waitlist Pro plugin for WordPress is vulnerable to Insecure Direct Object Reference via the wc-instocknotifier/v3/update_subscriber and create_subscriber REST API routes in all versions up to, and including, 7.4.5, due to the routes' permission check relying on the publish_posts capability, which authors hold, and the update route not checking that the user-supplied 'ID' belongs to a subscriber record before passing it to wp_update_post(). This makes it possible for authenticated attackers, with Author-level access and above, to create and modify waitlist subscriber records, and to change the post type and status of any post, page or product to a subscriber record and add the plugin's metadata to it. This removes that content from the site.

## References

- https://wpsec.com/vuln/WPSEC-2026-1117/
- https://plugins.svn.wordpress.org/back-in-stock-notifier-for-woocommerce/tags/7.5.0/
- https://wordpress.org/plugins/back-in-stock-notifier-for-woocommerce/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-1117/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.