Back in September, the developer of the 2+ million WordPress plugin MC4WP: Mailchimp for WordPress and Wordfence claimed that a minor vulnerability had been fixed. The fix was obviously incomplete and it turns out the issue is wider than that.

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This post provides insights on a vulnerability in the WordPress plugin MC4WP: Mailchimp for WordPress not discovered by us, where the discoverer hadn't provided the details needed for us to confirm the vulnerability while we were adding it to the data set for our service, so the rest of its contents are limited to subscribers of our service.

If you were using our service, you would have already been warned about this vulnerability if your website is vulnerable due to it. You can try out our service for free and then see the rest of the details of the vulnerability.

For existing customers, please log in to your account to view the rest of the contents of the post.

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Plugin Security Scorecard Grade for MC4WP: Mailchimp for WordPress

Checked on March 14, 2025

See issues causing the plugin to get less than A+ grade