Reported vulnerability

GutenKit <= 2.4.12 - Missing Authorization to Unauthenticated Sensitive Information Exposure via Mailchimp REST Endpoints

Published 22 Jul 2026

Updated 23 Jul 2026

CVE-2026-15827

Compare your installed software with the affected versions below. Follow the source’s remediation guidance and test an available update after taking a backup. A database entry describes a reported issue; it does not establish whether a particular website has been compromised.

Does this affect my version?

Check your installed version against this advisory. This compares the report’s version ranges and does not scan your website.

Wordfence advisory

medium · CVSS 5.3

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.

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

GutenKit – Page Builder Blocks, Patterns, and Templates for Gutenberg Block Editor

Software: plugin · gutenkit-blocks-addon
Affected versions: Start version unspecified, through 2.4.12
Fix availability: Fix available
Fixed versions: 2.4.13

Recommended action

Update to version 2.4.13, or a newer patched version

Further references (1)

wordfence.com/threat-intel/vulnerabilities/id/7430594c-3a71-4b24-875b-014e03be868f?source=api-prod

Data sources and licences

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CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.

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Source: Wordfence

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Questions about this vulnerability

Which versions of GutenKit – Page Builder Blocks, Patterns, and Templates for Gutenberg Block Editor are affected?

Wordfence lists these affected versions: Start version unspecified, through 2.4.12. Use the version checker above to compare your installed release with this report.

Is a fix available for GutenKit – Page Builder Blocks, Patterns, and Templates for Gutenberg Block Editor?

Wordfence reports a fix for this issue in GutenKit – Page Builder Blocks, Patterns, and Templates for Gutenberg Block Editor. It lists these fixed versions: 2.4.13. Back up your website and test the recommended update before applying it to your live site.

Where can I find my installed plugin version?

In WordPress, open Plugins > Installed Plugins and find the version shown beneath the plugin name.

Does an affected version mean my website has been hacked?

An affected version means the installed release matches a vulnerability described in this report. It does not show whether anyone has exploited it on your website. The checker compares version numbers with stored reports; it does not inspect your website.

These reports cover at least one of the same plugins, themes or WordPress core. Check each report’s affected versions separately.

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