CVE-2026-15827 — MEDIUM (5.3)

Vulnerability 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.

CVSS Score

5.3

MEDIUM

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

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

LOW

Integrity

NONE

Availability

NONE

Related Weaknesses (CWE)

CWE-862

References

FAQ

What is CVE-2026-15827?

CVE-2026-15827 is a vulnerability with a CVSS score of 5.3 (MEDIUM). 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/mailchi...

How severe is CVE-2026-15827?

CVE-2026-15827 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-15827?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.