{"id":"GHSA-crpf-4hrx-3jrp","summary":"Svelte SSR attribute spreading includes inherited properties from prototype chain","details":"In server-side rendering, attribute spreading on elements (e.g. `\u003cdiv {...attrs}\u003e`) enumerates inherited properties from the object's prototype chain rather than only own properties. In environments where `Object.prototype` has already been polluted — a precondition outside of Svelte's control — this can cause unexpected attributes to appear in SSR output or cause SSR to throw errors. Client-side rendering is not affected.","aliases":["CVE-2026-27125"],"modified":"2026-07-17T21:10:28.681038777Z","published":"2026-02-19T20:28:49Z","database_specific":{"github_reviewed":true,"github_reviewed_at":"2026-02-19T20:28:49Z","nvd_published_at":"2026-02-20T23:16:02Z","cwe_ids":["CWE-915"],"severity":"MODERATE"},"references":[{"type":"WEB","url":"https://github.com/sveltejs/svelte/security/advisories/GHSA-crpf-4hrx-3jrp"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-27125"},{"type":"WEB","url":"https://github.com/sveltejs/svelte/commit/73098bb26c6f06e7fd1b0746d817d2c5ee90755f"},{"type":"PACKAGE","url":"https://github.com/sveltejs/svelte"},{"type":"WEB","url":"https://github.com/sveltejs/svelte/releases/tag/svelte@5.51.5"}],"affected":[{"package":{"name":"svelte","ecosystem":"npm","purl":"pkg:npm/svelte"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"5.51.5"}]}],"database_specific":{"last_known_affected_version_range":"\u003c= 5.51.4","source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-crpf-4hrx-3jrp/GHSA-crpf-4hrx-3jrp.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:H/SI:H/SA:N"}]}