Arbitrary file upload in Gravity Forms
CVE-2026-84434
The Gravity Forms plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 3.1.0.4 via the upload_file function. This is due to a mismatch between the field validation pipeline and the file persistence pipeline, where hidden file upload fields bypass extension validation and a rejected file's intact upload state is later passed to upload_file() without re-validation. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible. Exploitation requires the targeted form to contain a File Upload field with its Visibility set to 'Hidden'; the vulnerability is reachable by unauthenticated attackers on any publicly accessible form meeting this condition.
Vulnerability class: Unrestricted File Upload
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-84434?
- CVE-2026-84434 is a critical-severity vulnerability in Gravity Forms, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2026-09-19.
- How severe is CVE-2026-84434?
- Critical severity. CVSS v3 base score is 9.8 out of 10.