CVE-2026-128123

Description

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From version 5.5.7 until versions 5.5.8 and 6.0.1, , @sveltejs/adapter-node can attempt to add a header to an immutable request in a context that causes the server to crash, denying service to any other requests routed to that server. This issue is fixed in 5.5.8 and 6.0.1.

References

• https://github.com/sveltejs/kit/commit/04756a1f7a4f73e34f1934895340a46de84fc164
• https://github.com/sveltejs/kit/commit/0a2e58cbccdd46cac20aa5af4e2edf17e0da11dd
• https://github.com/sveltejs/kit/pull/17620
• https://github.com/sveltejs/kit/releases/tag/@sveltejs/adapter-node@5.5.8
• https://github.com/sveltejs/kit/releases/tag/@sveltejs/adapter-node@6.0.1