# CVE-2026-118166: MC4WP: Mailchimp for WordPress < 4.15.0 - Unauthenticated Arbitrary Shortcode Execution via Dynamic Content Tag

Status: published. Published: 2026-11-06. Updated: 2026-11-06.

The MC4WP: Mailchimp for WordPress WordPress plugin before 4.15.0 does not prevent request-derived values in its dynamic content tags from being processed as shortcodes when a form is embedded with its block, allowing unauthenticated visitors to execute arbitrary registered shortcodes with attacker-chosen attributes. This requires the site owner to have added a request-derived tag to the form content and to embed the form with the block rather than the classic shortcode.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Unknown / MC4WP: Mailchimp for WordPress: ≥ 0; < 4.15.0 (affected, semver). Source: CNA: WPScan

## Severity and prioritization

- CVSS 3.1: 4.8 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N; source: CNA: WPScan

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-74

## Exploit evidence

- exploit: https://wpscan.com/vulnerability/a8b2a564-25ae-4ed8-9c2c-989b104ba4c8/ (CNA: WPScan)

## References

- https://wpscan.com/vulnerability/a8b2a564-25ae-4ed8-9c2c-989b104ba4c8/ (CNA: WPScan; exploit, vdb-entry, technical-description)

## Provenance

- CNA: WPScan: https://www.cve.org/CVERecord?id=CVE-2026-118166; retrieved 2026-11-06; source updated 2026-11-06

Revision: 5090fd72fe936cf7473875dbd183d75d80daed12771b55b6991ff8a455fc20bc

Canonical: https://y2.dev/cve/CVE-2026-118166

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