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CVE-2026-63429
Published:July 20, 2026
Updated:August 04, 2026
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.
Affected Packages
https://github.com/heyform/heyform.git (GITHUB):
Affected version(s) >=v0.0.1 <v3.0.0-rc.9
Fix Suggestion:
Update to version v3.0.0-rc.9
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CVSS v4
Base Score:
8.8
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
HIGH
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
8.6
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
HIGH
Availability
LOW
Weakness Type (CWE)
Unrestricted Upload of File with Dangerous Type
Missing Authentication for Critical Function
EPSS
Base Score:
0.30