VULNERABILITY INTELLIGENCE

CVE-2026-45797

CVSS score6.4 MEDIUM

EPSS probability0.57%

CISA KEVNot currently listed

Published2026-07-20

Last modified2026-07-22

Description

HeyForm is an open-source form builder. Prior to version 3.0.0-rc.7, the `/api/upload` endpoint allows unauthenticated file uploads including SVG files. Uploaded SVGs are stored in the static assets directory and served with `Content-Type: image/svg+xml` by Express's serve-static middleware, allowing an attacker to achieve stored cross-site scripting (XSS) on the heyform domain without any authentication. Version 3.0.0-rc.7 contains a patch for the issue.