No VulnCrest analysis published for this CVE yet. Below is the original CNA/NVD description, unmodified.
Description
HeyForm is an open-source form builder. Prior to 3.0.1, /api/upload accepts a file according to the client-controlled multipart file.mimetype while retaining an HTML filename, and static/upload serves the resulting file as text/html with contentSecurityPolicy: false. An ordinary user can therefore upload active HTML that executes on the HeyForm origin when a victim opens its returned URL. The same-origin script can access /graphql with the victim's session and read or modify data available to that account. The code also permits upload requests tied to an active public form through formId, openToken, and a fieldId belonging to a file or signature question, although the advisory did not fully verify that unauthenticated path end to end. This issue is fixed in version 3.0.1.
Exploits & detection
No public PoC or detection template found yet.
Timeline
- Published: 05 Nov 2026
- Last modified upstream: 05 Nov 2026
Sources & licenses
- CVE / CVSS / CWE
- NVD record ↗ (unmodified). This product uses the NVD API but is not endorsed or certified by the NVD. CVE® © The MITRE Corporation.
- Exploitation
- CISA KEV (CC0) · EPSS by FIRST.org
- References used for the analysis
- Analysis, summary and remediation
- © VulnCrest