CVE-2026-40073

SvelteKit has a BODY_SIZE_LIMIT bypass in @sveltejs/adapter-node

8.2 HighFix available

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

0.54%Up 0.5 points since Apr 11, 2026

What each source reports

CVE List Score used 8.2

SvelteKit has a BODY_SIZE_LIMIT bypass in @sveltejs/adapter-node

Record: CVE-2026-40073
CVSS 4.0: 8.2 HighCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness: CWE-770
Updated: 2026-11-02

EUVDEUVD-2026-21502 8.2

Record: EUVD-2026-21502
CVSS 4.0: 8.2 HighCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Updated: 2026-11-02

GitHub AdvisoriesGHSA-2crg-3p73-43xp 8.2

@sveltejs/adapter-node has a BODY_SIZE_LIMIT bypass

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.

Record: GHSA-2crg-3p73-43xp
CVSS 4.0: 8.2 HighCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness: CWE-770
Updated: 2026-11-02

NVD 8.2

Record: CVE-2026-40073
CVSS 4.0: 8.2 HighCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-770
Updated: 2026-11-02

OSV 8.2

SvelteKit has a BODY_SIZE_LIMIT bypass in @sveltejs/adapter-node

Record: CVE-2026-40073
CVSS 4.0: 8.2 HighCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness: CWE-770
Updated: 2026-11-02

OSVGHSA-2crg-3p73-43xp 8.2

@sveltejs/adapter-node has a BODY_SIZE_LIMIT bypass

Record: GHSA-2crg-3p73-43xp
CVSS 4.0: 8.2 HighCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness: CWE-770
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`@sveltejs/kit` npm	through 2.57.0	2.57.1
`@sveltejs/kit` npm	before 2.57.1	2.57.1

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-40073 is a high vulnerability (CVSS 8.2) in Svelte Kit, published April 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.54%, the 45th percentile. Fixed in @sveltejs/kit 2.57.1.