Vulnerability · Published Aug 28, 2026 · Assigned by VulnCheck
CVE-2026-82291HeyForm Reflects Any Origin in CORS Responses While Allowing Credentials
High 8.1
In plain English
A high-severity security flaw in heyform from heyform. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 46% of all known vulnerabilities).
Severity (CVSS 3.1)8.1High
Exploit odds (30 days)0.6%top 53.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
HeyForm before 3.0.0-rc.8 reflects the request Origin header in CORS responses while allowing credentials, enabling cross-origin requests with authentication. Attackers can execute authenticated GraphQL queries from malicious pages visited by logged-in users to access workspaces, projects, forms, submissions, and respondent data, or modify account settings.
Affected products (as reported)
Weakness: CWE-942 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
References
- GitHub Security Advisory (GHSA-fg7j-rmgr-rc9g) vendor-advisory
- Vulnerable code: main.ts technical-description
- Fix commit patch
- https://github.com/heyform/heyform product
- VulnCheck Advisory: HeyForm Reflects Any Origin in CORS Responses While Allowing Credentials third-party-advisory