# CVE-2026-118167: MC4WP: Mailchimp for WordPress audience validation bypass

Source: https://junglewise.ai/threats/cve-2026-118167-the-mc4wp-mailchimp-for-wordpress-plugin-before-4-15-0-does-not  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-06. Updated: 2026-11-06  
License: CC BY 4.0 with a link back

CVE-2026-118167 · Severity: info · Published 2026-11-06

MC4WP is a WordPress plugin that integrates Mailchimp email marketing services into websites. The plugin before version 4.15.0 fails to verify which Mailchimp audience (contact list) a sign-up form should subscribe visitors to, allowing attackers to subscribe arbitrary email addresses to any audience in the site owner's Mailchimp account without authentication. This can lead to unauthorized contact list manipulation and potential spam or social engineering attacks.

Technologies: [MC4WP Mailchimp for WordPress](https://junglewise.ai/threats/technologies/mailchimp-for-wordpress). Vendors: [MC4WP](https://junglewise.ai/threats/vendors/mc4wp).

## Quick answers

**Is CVE-2026-118167 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-118167 being exploited in the wild.

**How severe is CVE-2026-118167?** Informational severity, published 6 November 2026.

**Which products and versions are affected?** MC4WP Mailchimp for WordPress before 4.15.0.

**Is there a fix for CVE-2026-118167?** Yes: fixed in 4.15.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-118167 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-118167?** Check whether you run MC4WP Mailchimp for WordPress at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in 4.15.0

## Technical details

The vulnerability is an incorrect authorization flaw (CWE-863) where the plugin does not validate that the audience ID in a sign-up form request matches the audience configured by the site owner. An unauthenticated attacker can craft requests to subscribe arbitrary email addresses to any audience within the connected Mailchimp account by manipulating the audience parameter. The fix is available in version 4.15.0.

## Affected products

- MC4WP Mailchimp for WordPress before 4.15.0

## Timeline

- 2026-11-04: disclosed
- 2026-11-06: advisory

## References

- [https://wpscan.com/vulnerability/11752539-1dc8-4adb-a680-ce7ecaaff4d1/](https://wpscan.com/vulnerability/11752539-1dc8-4adb-a680-ce7ecaaff4d1/)

## Related threats

- [MC4WP: Mailchimp for WordPress reflected cross-site scripting](https://junglewise.ai/threats/cve-2026-87917-the-mc4wp-mailchimp-for-wordpress-plugin-for-wordpress-is)
- [MC4WP: Mailchimp for WordPress stored cross-site scripting in form response messages](https://junglewise.ai/threats/cve-2026-4561-mc4wp-mailchimp-for-wordpress-stored-cross-site-scripting-in-form)