CVE-2026-66062

Description

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to 2.70.2, the content negotiation header parser used by SvelteKit's request handling (for headers such as Accept) uses a regular expression vulnerable to quadratic backtracking, so a maliciously crafted header value can cause excessive CPU consumption and degrade or deny service. Version 2.70.2 fixes the issue.

CVSS Vector

References

• https://github.com/sveltejs/kit/commit/82712fc02c24b1dcf5b25d7a52129cd8455f04f5
• https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.70.2
• https://github.com/sveltejs/kit/security/advisories/GHSA-29g2-3rmr-qm68