CVE-2026-87917 json
MC4WP: Mailchimp for WordPress <= 4.14.0 - Reflected Cross-Site Scripting via 'data' Dynamic Content Tag
published last mo. modified last mo. also EUVD-2026-83559
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 32%
- public exploits
- 0
- none known
Summary
The MC4WP: Mailchimp for WordPress plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via 'data' Dynamic Content Tag in all versions up to, and including, 4.14.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.38% chance of exploitation in the next 30 days, higher than 32% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected products
- dvankooten MC4WP: Mailchimp for WordPress
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/ee4f837a-d0b5-48df-8c96-2a294985612e?source=cve
- plugins.trac.wordpress.org /browser/mailchimp-for-wp/tags/4.14.0/includes/class-dynamic-content-tags.php#L127
- plugins.trac.wordpress.org /browser/mailchimp-for-wp/tags/4.14.0/includes/forms/class-form-tags.php#L57
- plugins.trac.wordpress.org /browser/mailchimp-for-wp/tags/4.14.0/includes/forms/class-form-tags.php#L109
- plugins.trac.wordpress.org /changeset?reponame=&new=3689679%40mailchimp-for-wp%2Ftags%2F4.14.1&old=3655905%40mailchimp-for-wp%2Ftags%2F4.
- plugins.trac.wordpress.org /changeset?reponame=&new=3698084%40mailchimp-for-wp%2Ftags%2F4.14.1&old=3655905%40mailchimp-for-wp%2Ftags%2F4.
Sources
- CVE List CVE-2026-87917
- NVD CVE-2026-87917
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