{"id":"CVE-2026-66062","state":"PUBLISHED","title":"SvelteKit: ReDoS (O(n^2)) in content negotiation — unauthenticated DoS via the Accept header","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.","publishedAt":"2026-08-07T16:49:43.853Z","updatedAt":"2026-08-07T21:02:12.997Z","severity":{"score":5.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["sveltejs kit"],"affected":[{"vendor":"sveltejs","product":"kit","versions":[{"version":"< 2.70.2","status":"affected"}]}],"references":["https://github.com/sveltejs/kit/security/advisories/GHSA-29g2-3rmr-qm68","https://github.com/sveltejs/kit/commit/82712fc02c24b1dcf5b25d7a52129cd8455f04f5","https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.70.2"],"weaknesses":["CWE-1333"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/66xxx/CVE-2026-66062.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-66062","state":"PUBLISHED","datePublished":"2026-08-07T16:49:43.853Z","dateUpdated":"2026-08-07T21:02:12.997Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-23T23:25:28.896Z"},"containers":{"cna":{"title":"SvelteKit: ReDoS (O(n^2)) in content negotiation — unauthenticated DoS via the Accept header","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"sveltejs","product":"kit","versions":[{"version":"< 2.70.2","status":"affected"}]}],"references":[{"url":"https://github.com/sveltejs/kit/security/advisories/GHSA-29g2-3rmr-qm68","name":"https://github.com/sveltejs/kit/security/advisories/GHSA-29g2-3rmr-qm68","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/sveltejs/kit/commit/82712fc02c24b1dcf5b25d7a52129cd8455f04f5","name":"https://github.com/sveltejs/kit/commit/82712fc02c24b1dcf5b25d7a52129cd8455f04f5","tags":["x_refsource_MISC"]},{"url":"https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.70.2","name":"https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.70.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1333","lang":"en","description":"CWE-1333: Inefficient Regular Expression Complexity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-07T16:49:43.853Z"},"source":{"advisory":"GHSA-29g2-3rmr-qm68","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-07T20:58:04.458547Z","id":"CVE-2026-66062","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-07T21:02:12.997Z"}}]}}}