VulnerabilityAnalyzed

CVE-2026-40074

This vulnerability is fixed in 2.57.1.

MEDIUM 6.3EPSS 0.37%

Does this matter?

Lower severity and a low EPSS score (0.37%). Track it; it rarely justifies an emergency change on its own.

Description

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to 2.57.1, redirect, when called from inside the handle server hook with a location parameter containing characters that are invalid in a HTTP header, will cause an unhandled TypeError. This could result in DoS on some platforms, especially if the location passed to redirect contains unsanitized user input. This vulnerability is fixed in 2.57.1.

CVSS 4.0: 6.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.37% probability · 30th percentile
CISA KEV: Not listed
Weakness: CWE-755
Affected: svelte/kit
Source: security-advisories@github.com

References

https://github.com/sveltejs/kit/commit/10d7b44425c3d9da642eecce373d0c6ef83b4fcdPatch
https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.57.1Product, Release Notes
https://github.com/sveltejs/kit/security/advisories/GHSA-3f6h-2hrp-w5wxVendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.