CVE-2026-19513 Gravity Forms <= 3.0.2 - Unauthenticated Arbitrary File Upload via State/Chunk Hash Confusion
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-19513?
CVE-2026-19513 is a high-severity vulnerability in Gravity Forms, published on 1 Sep 2026.
Official description
The Gravity Forms plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 3.0.2. This is due to insufficient validation of multi-file upload chunk state in the `GFAsyncUpload::upload()` function, where public form state URL hashes can be reused as chunk continuation hashes and attacker-controlled temporary filenames are accepted before sanitization. This makes it possible for unauthenticated attackers, when a public form contains a File Upload field with Multiple Files enabled, to upload a valid PNG/PDF polyglot to an attacker-selected public `.php` or `.html` filename in the Gravity Forms temporary upload directory. This can lead to remote code execution on WordPress systems that use NGINX or other non `.htaccess` respecting web servers. NOTE: During installation and activation, the Gravity Forms plugin places a `.htaccess` file in this directory, which prevents this vulnerability from being exploited despite the PHP file being written to the temporary upload directory. In these cases where PHP execution is blocked, attacker-written HTML can result in stored same-origin cross-site scripting if a victim visits the generated file URL.
Weakness: CWE-434
Which versions are affected by CVE-2026-19513?
How do I fix CVE-2026-19513?
No fix has been published for CVE-2026-19513 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-19513 being exploited?
There is no known exploitation of CVE-2026-19513 in the wild and no public exploit code.
Sources
Also known as GHSA-fjj9-76vm-r7vp.