Origin Validation Error Affecting next package, versions >=16.0.0 <16.3.8
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-JS-NEXT-20569642
- published8 Oct 2026
- disclosed2 Oct 2026
- creditUnknown
Introduced: 2 Oct 2026
NewCVE-2026-94485 (opens in a new tab)How to fix?
Upgrade next to version 16.3.8 or higher.
Overview
next is a react framework.
Affected versions of this package are vulnerable to Origin Validation Error via the MCP middleware endpoint /_next/mcp, where insufficient host validation allows a DNS rebinding attack. An attacker who controls a malicious DNS server can cause a victim's browser to treat the attacker's domain as a same-origin resource, bypassing the cross-site request protections applied in development mode and gaining read access to confidential data exposed by the MCP server.