# Ultimate Product Catalog <= 5.4.0 - Cross-Site Request Forgery to Custom Field Definitions Update

- **ID:** WPSEC-2026-0958
- **Plugin:** Ultimate Product Catalog (`ultimate-product-catalogue`), https://wordpress.org/plugins/ultimate-product-catalogue/
- **Affected versions:** all versions before 5.5.0
- **Fixed in:** 5.5.0 (Update to 5.5.0 or later.)
- **Severity:** Medium 4.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N)
- **Weakness:** CWE-352
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-10-14)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/ultimate-product-catalogue
- **Fix released:** 2026-10-13
- **Published:** 2026-10-14
- **URL:** https://wpsec.com/vuln/WPSEC-2026-0958/

## Description

The Ultimate Product Catalog plugin for WordPress is vulnerable to Cross-Site Request Forgery via the Custom Fields admin page in all versions up to, and including, 5.4.0, due to missing nonce validation in the save_custom_fields() function. This makes it possible for unauthenticated attackers to overwrite the catalog's custom field definitions through a forged request, if they can trick a site administrator into performing an action such as clicking a link. The custom fields feature must be enabled through the plugin's premium license.

## References

- https://wpsec.com/vuln/WPSEC-2026-0958/
- https://plugins.svn.wordpress.org/ultimate-product-catalogue/tags/5.5.0/
- https://wordpress.org/plugins/ultimate-product-catalogue/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-0958/

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.