{"id":"CVE-2026-66062","title":"SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte","summary":"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 exp…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","cwe":["CWE-1333"],"vendor":"sveltejs","product":"@sveltejs/kit","affected":["@sveltejs/kit <= 2.70.1"],"patched":["@sveltejs/kit 2.70.2"],"published":"2026-08-07","updated":"2026-09-09","sourceUpdated":"2026-09-09T21:02:22.660","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-66062","references":[{"url":"https://github.com/sveltejs/kit/commit/82712fc02c24b1dcf5b25d7a52129cd8455f04f5","label":"security-advisories@github.com"},{"url":"https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.70.2","label":"security-advisories@github.com"},{"url":"https://github.com/sveltejs/kit/security/advisories/GHSA-29g2-3rmr-qm68","label":"security-advisories@github.com"},{"url":"https://github.com/advisories/GHSA-29g2-3rmr-qm68"}],"tags":["nvd","ghsa","npm"],"epss":0.00291,"epssPercentile":0.21975,"aliases":["GHSA-29g2-3rmr-qm68"],"ecosystem":"npm","ingestedAt":"2026-08-07T17:15:34.094Z","slug":"CVE-2026-66062","body":"## Overview\n\nSvelteKit 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-66062)\n\nAffected packages:\n\n- `@sveltejs/kit <= 2.70.1`\n\nPatched in:\n\n- `@sveltejs/kit 2.70.2`\n\nSource: https://github.com/advisories/GHSA-29g2-3rmr-qm68","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}