What’s Vulnerable › Vulnerabilities

CVE-2026-2428: Fluent Forms Pro Add On Pack <= 6.1.17 - Missing Authorization to Unauthenticated Payment Status modification

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-02-27 · updated 2026-06-17
• Weakness: CWE-345

Description

The Fluent Forms Pro Add On Pack plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in all versions up to, and including, 6.1.17. This is due to the PayPal IPN (Instant Payment Notification) verification being disabled by default (`disable_ipn_verification` defaults to `'yes'` in `PayPalSettings.php`). This makes it possible for unauthenticated attackers to send forged PayPal IPN notifications to the publicly accessible IPN endpoint, marking unpaid form submissions as "paid" and triggering post-payment automation (emails, access grants, digital product delivery).

Affected products

• techjewel Fluent Forms Pro Add On Pack: through 6.1.17

References

• https://fluentforms.com/docs/changelog/#2-toc-title
• https://www.wordfence.com/threat-intel/vulnerabilities/id/e5c62e54-da06-4b44-ba70-63065e664b0d?source=cve

Get alerted when CVE-2026-2428 or the next vulnerability affects your stack