Read the docs
TI-2026-85749 Aliases CVE-2026-118167GHSA-qpwm-gvfh-p35v

Incorrect authorization in MC4WP Mailchimp for WordPress plugin

Priority LOW 29CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-863.

Summary

The MC4WP: Mailchimp for WordPress plugin before 4.15.0 does not check that the Mailchimp audience a sign-up form or bundled integration subscribes a visitor to matches the audience the site owner configured. An unauthenticated visitor can subscribe arbitrary email addresses to any other audience in the site's connected Mailchimp account. The flaw is tracked as CWE-863 (Incorrect Authorization). An exploit is linked in the references.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

The MC4WP: Mailchimp for WordPress plugin before 4.15.0 does not validate that the Mailchimp audience a sign-up form or bundled integration subscribes a visitor to matches the audience configured by the site owner, allowing unauthenticated visitors to subscribe arbitrary email addresses to any other audience in the site's connected Mailchimp account.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00214 11th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix Fixed MC4WP: Mailchimp for WordPress (Unknown): 4.15.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
UnknownMC4WP: Mailchimp for WordPressbefore 4.15.04.15.0Patch availableCNA
  • MC4WP: Mailchimp for WordPress VendorUnknown Affected before 4.15.0 Fixed in 4.15.0 Patch available CNA

Remediation

Update MC4WP: Mailchimp for WordPress to version 4.15.0 or later.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA MC4WP: Mailchimp for WordPress (Unknown) Fixed in 4.15.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    MC4WP: Mailchimp for WordPress 4.15.0

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-85767 MC4WP Mailchimp for WordPress: Unauthenticated Shortcode ExecutionPriority LOW 21
    Show all 2 records →

Timeline

  1. 2026-11-06 Threatist record created from CVE-2026-118167
  2. 2026-11-06 Alias added: GHSA-qpwm-gvfh-p35v
  3. 2026-11-06 CVSS score added · CISA ADP
  4. 2026-11-06 Weakness changed · CISA ADP
  5. 2026-11-06 CISA SSVC decision points changed

References

Exploit 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences