CVE-2026-19513
Gravity Forms <= 3.0.2 - Unauthenticated Arbitrary File Upload via State/Chunk Hash Confusion
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.
INFO
Published Date :
Sept. 1, 2026, 2:17 p.m.
Last Modified :
Sept. 1, 2026, 3:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-19513
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE |
Solution
- Update Gravity Forms plugin to the latest version.
- Ensure the .htaccess file is present in the uploads directory.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-19513.
| URL | Resource |
|---|---|
| https://docs.gravityforms.com/gravityforms-change-log/ | |
| https://www.wordfence.com/threat-intel/vulnerabilities/id/d20b2d00-054e-4772-a5a5-b7b33063043c?source=cve |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-19513 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-19513
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-19513 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-19513 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 01, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-19513', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-01T14:17:05.669639Z'} -
New CVE Received by [email protected]
Sep. 01, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-434 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/19xxx/CVE-2026-19513.json">CVE-2026-19513</a> Added Reference https://docs.gravityforms.com/gravityforms-change-log/ Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/d20b2d00-054e-4772-a5a5-b7b33063043c?source=cve