8.6
HIGH CVSS 3.1
CVE-2026-63429
HeyForm has unauthenticated /api/upload endpoint that accepts arbitrary files with no auth/session/form context
Description

HeyForm is an open-source form builder. Prior to version 3.0.0-rc.9, `POST /api/upload` has no authentication guard, no global guard, no form-context validation, no `openToken` requirement, and no session cookie check. Any anonymous internet user can upload files (PDF, DOC/DOCX, XLS/XLSX, CSV, TXT, MP4, images, etc., up to 10 MB) and receive a permanent public URL on the HeyForm domain. The endpoint is used by both authenticated form creators and unauthenticated form submitters; because no form-context binding exists, every request to it is anonymously accepted. Version 3.0.0-rc.9 contains a patch for the issue.

INFO

Published Date :

July 20, 2026, 4:17 p.m.

Last Modified :

July 20, 2026, 6:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-63429 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
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH [email protected]
Solution
Update HeyForm to version 3.0.0-rc.9 or later to address the authentication bypass vulnerability.
  • Update HeyForm to version 3.0.0-rc.9 or later.
  • Ensure upload endpoint has proper authentication checks.
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-2026-63429.

URL Resource
https://github.com/heyform/heyform/commit/092e255e9e02565de1b3c057f3dad849160952d2
https://github.com/heyform/heyform/security/advisories/GHSA-432x-54v2-p7p7
https://github.com/heyform/heyform/security/advisories/GHSA-432x-54v2-p7p7
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63429 is associated with the following CWEs:

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-2026-63429 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-63429 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

    Jul. 20, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/heyform/heyform/security/advisories/GHSA-432x-54v2-p7p7
    Added SSVC {'id': 'CVE-2026-63429', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-20T17:45:12.280558Z'}
  • New CVE Received by [email protected]

    Jul. 20, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'heyform', 'product': 'heyform', 'versions': [{'status': 'affected', 'version': '< 3.0.0-rc.9'}]}]
    Added Description HeyForm is an open-source form builder. Prior to version 3.0.0-rc.9, `POST /api/upload` has no authentication guard, no global guard, no form-context validation, no `openToken` requirement, and no session cookie check. Any anonymous internet user can upload files (PDF, DOC/DOCX, XLS/XLSX, CSV, TXT, MP4, images, etc., up to 10 MB) and receive a permanent public URL on the HeyForm domain. The endpoint is used by both authenticated form creators and unauthenticated form submitters; because no form-context binding exists, every request to it is anonymously accepted. Version 3.0.0-rc.9 contains a patch for the issue.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
    Added CWE CWE-306
    Added CWE CWE-434
    Added Reference https://github.com/heyform/heyform/commit/092e255e9e02565de1b3c057f3dad849160952d2
    Added Reference https://github.com/heyform/heyform/security/advisories/GHSA-432x-54v2-p7p7
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.