What is CVE-2026-40073?

CVE-2026-40073 is a high-severity vulnerability in Svelte Kit, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-04-10.

How severe is CVE-2026-40073?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Svelte Kit

CVE-2026-40073

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to 2.57.1, under certain circumstances, requests could bypass the BODY_SIZE_LIMIT on SvelteKit applications running with adapter-node. This bypass does not affect body size limits at other layers of the application stack, so limits enforced in the WAF, gateway, or at the platform level are unaffected. This vulnerability is fixed in 2.57.1.

Published 2026-04-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (44.5th percentile), scored 2026-09-23.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Svelte Kit
Sveltejs Kit — versions < 2.57.1

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

github.com/sveltejs/kit/security/advisories/GHSA-2crg-3p73-43xp (Vendor Advisory)
github.com/sveltejs/kit/commit/3202ed6c98f9e8d86bf0c4c7ad0f2e273e5e3b95 (Patch)
github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.57.1 (Product, Release Notes)

Frequently asked questions

What is CVE-2026-40073?: CVE-2026-40073 is a high-severity vulnerability in Svelte Kit, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-04-10.
How severe is CVE-2026-40073?: High severity. CVSS v3 base score is 7.5 out of 10.