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CVE-2026-87917: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in dvankooten MC4WP: Mailchimp for WordPress

0
Medium
VulnerabilityCVE-2026-87917cvecve-2026-87917cwe-79
Published: 09/19/2026 (09/19/2026, 07:43:20 UTC)
Source: CVE Database V5
Vendor/Project: dvankooten
Product: MC4WP: Mailchimp for WordPress

Description

MC4WP: Mailchimp for WordPress plugin versions up to and including 4.14.0 are vulnerable to reflected Cross-Site Scripting (XSS) via the 'data' Dynamic Content Tag. This vulnerability arises from insufficient input sanitization and output escaping, allowing unauthenticated attackers to inject arbitrary scripts that execute when a user interacts with crafted content.

CVSS v3.1

Score 6.1medium

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected software

dvankooten

MC4WP: Mailchimp for WordPress

Affected versions
>=0 <=4.14.0

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/19/2026, 08:02:02 UTC

Technical Analysis

The MC4WP: Mailchimp for WordPress plugin suffers from a reflected Cross-Site Scripting vulnerability (CWE-79) in all versions up to 4.14.0. The flaw is due to improper neutralization of input in the 'data' Dynamic Content Tag, enabling unauthenticated attackers to inject malicious scripts. Exploitation requires tricking a user into performing an action such as clicking a link, leading to script execution in the user's browser context.

Potential Impact

Successful exploitation can lead to partial confidentiality and integrity loss (as indicated by CVSS: C:L/I:L), allowing attackers to execute arbitrary scripts in the context of the affected site. This may result in session hijacking, defacement, or other client-side attacks. Availability is not impacted. The vulnerability requires user interaction but no privileges or authentication.

Mitigation Recommendations

No explicit patch or remediation details are provided in the input data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is applied, users should consider disabling or restricting use of the 'data' Dynamic Content Tag or applying web application firewall rules to block malicious input patterns.

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Technical Details

Data Version
5.2
Assigner Short Name
Wordfence
Date Reserved
2026-09-09T15:56:01.475Z
Cvss Version
3.1
State
PUBLISHED

Threat ID: 6aae3e0455bf5e2cf54897db

Added to database: 09/19/2026, 07:47:16 UTC

Last enriched: 09/19/2026, 08:02:02 UTC

Last updated: 09/19/2026, 08:29:02 UTC

Views: 5

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