CVE-2026-15827

medium

Description

The GutenKit Blocks plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the /wp-json/gutenkit/v1/mailchimp/get/lists and /wp-json/gutenkit/v1/mailchimp/get/interests REST API endpoints in versions up to, and including, 2.4.12. Both endpoints are registered with permission_callback => '__return_true', and their callbacks read the site's stored Mailchimp API key from the gutenkit_settings_list option and proxy Mailchimp audience/list, merge-field, interest-category, interest-name, and subscriber-count metadata back to the caller with no login, nonce, or capability check. This makes it possible for unauthenticated attackers to retrieve private Mailchimp audience configuration information from any site that has configured the GutenKit Mailchimp integration.

References

https://www.wordfence.com/threat-intel/vulnerabilities/id/7430594c-3a71-4b24-875b-014e03be868f?source=cve

https://plugins.trac.wordpress.org/changeset?reponame=&old=3618270%40gutenkit-blocks-addon&new=3618270%40gutenkit-blocks-addon

https://plugins.trac.wordpress.org/browser/gutenkit-blocks-addon/tags/2.4.6/includes/Routes/MailChimp.php#L62

https://plugins.trac.wordpress.org/browser/gutenkit-blocks-addon/tags/2.4.6/includes/Routes/MailChimp.php#L43

https://plugins.trac.wordpress.org/browser/gutenkit-blocks-addon/tags/2.4.6/includes/Routes/MailChimp.php#L17

https://plugins.trac.wordpress.org/browser/gutenkit-blocks-addon/tags/2.4.6/includes/Routes/MailChimp.php#L141

https://plugins.trac.wordpress.org/browser/gutenkit-blocks-addon/tags/2.4.11/includes/Routes/MailChimp.php#L62

https://plugins.trac.wordpress.org/browser/gutenkit-blocks-addon/tags/2.4.11/includes/Routes/MailChimp.php#L43

https://plugins.trac.wordpress.org/browser/gutenkit-blocks-addon/tags/2.4.11/includes/Routes/MailChimp.php#L17

https://plugins.trac.wordpress.org/browser/gutenkit-blocks-addon/tags/2.4.11/includes/Routes/MailChimp.php#L141

Details

Source: Mitre, NVD

Published: 2026-07-23

Updated: 2026-07-23

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 5.3

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Severity: Medium

EPSS

EPSS: 0.00539