What is CVE-2026-1303?

CVE-2026-1303 is a medium-severity vulnerability in Matthieuscarset Mailchimp Campaigns, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-02-14.

How severe is CVE-2026-1303?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Auth bypass in Matthieuscarset Mailchimp Campaigns

CVE-2026-1303

The MailChimp Campaigns plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 3.2.4. This is due to missing capability checks on the `mailchimp_campaigns_manager_disconnect_app` function that is hooked to the AJAX action of the same name. This makes it possible for authenticated attackers, with Subscriber-level access and above, to disconnect the site from its MailChimp synchronization app, disrupting automated email campaigns and marketing integrations.

Vulnerability class: Broken Access Control

EPSS: 0.003 (21.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

Affected products

Matthieuscarset Mailchimp Campaigns — versions 0

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

Frequently asked questions

What is CVE-2026-1303?: CVE-2026-1303 is a medium-severity vulnerability in Matthieuscarset Mailchimp Campaigns, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-02-14.
How severe is CVE-2026-1303?: Medium severity. CVSS v3 base score is 5.3 out of 10.