# CVE-2026-82291: HeyForm CORS misconfiguration with credential handling

Source: https://junglewise.ai/threats/cve-2026-82291-heyform-cors-misconfiguration-with-credential-handling  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-28. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-82291 · Severity: high · CVSS 8.1 · Published 2026-08-28

HeyForm is an open-source form builder used to create and manage web forms. The application incorrectly reflects user-supplied Origin headers in CORS responses while allowing credentials, enabling attackers to make authenticated requests from malicious websites. A logged-in user visiting a compromised page could have their form submissions, workspace data, projects, and account settings accessed or modified without authorization.

Technologies: [HeyForm](https://junglewise.ai/threats/technologies/heyform). Vendors: [HeyForm](https://junglewise.ai/threats/vendors/heyform).

## Quick answers

**Is CVE-2026-82291 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-82291 being exploited in the wild.

**How severe is CVE-2026-82291?** High severity, with a CVSS score of 8.1, published 28 August 2026.

**Which products and versions are affected?** HeyForm before 3.0.0-rc.8.

**Is there a fix for CVE-2026-82291?** A patch was published on 2026-08-28: Fixed in version 3.0.0-rc.8 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-82291 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-82291?** Check whether you run HeyForm at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a CORS misconfiguration where the application uses `origin: true` in the CORS policy combined with `credentials: true`, which causes the server to echo back the Origin header from any request and allow authentication cookies to be sent cross-origin. This violates the same-origin policy and enables cross-site request forgery (CSRF) attacks via authenticated GraphQL queries. An attacker can craft a malicious webpage that, when visited by an authenticated HeyForm user, executes arbitrary GraphQL queries with the victim's authentication context, accessing or modifying workspaces, projects, forms, submissions, and respondent data. The fix requires restricting the CORS origin to specific trusted domains rather than accepting all origins. The vulnerability affects HeyForm versions before 3.0.0-rc.8.

## Affected products

- HeyForm HeyForm before 3.0.0-rc.8

## Timeline

- 2026-08-28: disclosed
- 2026-08-28: patched: Fixed in version 3.0.0-rc.8

## References

- [https://github.com/heyform/heyform](https://github.com/heyform/heyform)
- [https://github.com/heyform/heyform/blob/v3.0.0-rc.7/packages/server/src/main.ts](https://github.com/heyform/heyform/blob/v3.0.0-rc.7/packages/server/src/main.ts)

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