CVE-2026-64649

A flaw was found in Next.js, a framework for building web applications. A remote attacker can exploit this vulnerability by manipulating Host-associated headers when a Server Action forwards or redirects a request. This can lead to Server-Side Request Forgery (SSRF), where the server is tricked into making requests to an attacker-controlled host. Such an attack could potentially expose internal system information or bypass authorization controls.

This Important Server-Side Request Forgery (SSRF) flaw in Next.js Server Actions allows an attacker to redirect outbound requests to a malicious host. This is particularly relevant for Red Hat customers deploying Next.js applications on custom servers or without a proxy that enforces host header validation, as it could lead to unauthorized internal network access or information disclosure. Managed hosting environments and applications using next start or standalone output from version 14.2 onwards are not affected.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.