Stored XSS Vulnerability in HeyForm Form Builder by HeyForm
CVE-2026-35198

9CRITICAL

Key Information:

Vendor

Heyform

Status
Heyform
Vendor
CVE Published:
20 July 2026

What is CVE-2026-35198?

Prior to version 3.0.0-rc.7, HeyForm, an open-source form builder, is vulnerable to a stored cross-site scripting (XSS) issue. This vulnerability allows low-privileged team members to inject malicious JavaScript code into the forms. When team owners view these forms, the injected script executes, creating a risk of complete account takeover through privilege escalation. Users are advised to upgrade to version 3.0.0-rc.7 or later, which addresses this vulnerability.

Affected Version(s)

heyform < 3.0.0-rc.7

References

https://github.com/heyform/heyform/security/advisories/GH...
x_refsource_CONFIRM
https://github.com/heyform/heyform/commit/cc97d27a57ae400...
x_refsource_MISC

CVSS V3.1

Score:
9
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
Required
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.