CVE-2025-67647: Svelte Adapter-Node

Critical severity, CVSS 9.1. EPSS: 0.5% chance of exploitation in the next 30 days.

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to 2.49.5, SvelteKit is vulnerable to a server side request forgery (SSRF) and denial of service (DoS) under certain conditions. From 2.44.0 through 2.49.4, the vulnerability results in a DoS when your app has at least one prerendered route (export const prerender = true). From 2.19.0 through 2.49.4, the vulnerability results in a DoS when your app has at least one prerendered route and you are using adapter-node without a configured ORIGIN environment variable, and you are not using a reverse proxy that implements Host header validation. This vulnerability is fixed in 2.49.5.

Affected products

• Svelte Adapter-Node: from 5.4.1, before 5.5.1 (fixed in 5.5.1)
• Svelte Kit: from 2.19.0, before 2.49.5 (fixed in 2.49.5)

Published 2026-01-15. Last modified 2026-06-17.