What’s Vulnerable › Vulnerabilities

CVE-2026-40073: SvelteKit has a BODY_SIZE_LIMIT bypass in @sveltejs/adapter-node

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-04-10 · updated 2026-10-25
• Weakness: CWE-770

Description

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.

Affected products

• Svelte Kit: before 2.57.1 — fixed in 2.57.1

How to fix

Upgrade to a fixed version: Svelte Kit 2.57.1. Check the vendor advisory for mitigations.

References

• https://github.com/sveltejs/kit/commit/3202ed6c98f9e8d86bf0c4c7ad0f2e273e5e3b95
• https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.57.1
• https://github.com/sveltejs/kit/security/advisories/GHSA-2crg-3p73-43xp

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