CVE-2026-4394: Gravity Forms <= 2.9.30 - Unauthenticated Stored Cross-Site Scripting via Credit Card 'Card Type' Sub-Field

Vulnerability summary

CVE-2026-4394 is a medium (CVSS 6.1) Cross-site Scripting vulnerability in gravity forms. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 30.7% of scored vulnerabilities. Fixed in 2.9.31.

Timeline

1. 07-04-2026
   PublishedVulnerability first disclosed.
2. 08-04-2026
   Last modifiedVulnerability information updated.

Description

The Gravity Forms plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Credit Card field's 'Card Type' sub-field (`input_<id>.4`) in all versions up to, and including, 2.9.30. This is due to the `get_value_entry_detail()` method in the `GF_Field_CreditCard` class outputting the card type value without escaping, combined with `get_value_save_entry()` accepting and storing unsanitized user input for the `input_<id>.4` parameter. The Card Type field is not rendered on the frontend form (it is normally derived from the card number), but the backend submission parser blindly accepts it if included in the POST request. This makes it possible for unauthenticated attackers to inject arbitrary web scripts that execute when an administrator views the form entry in the WordPress dashboard.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.