{"id":"CVE-2025-32388","aliases":["GHSA-6q87-84jw-cjhp"],"title":"@sveltejs/kit vulnerable to Cross-site Scripting via tracked search_params","summary":"@sveltejs/kit vulnerable to Cross-site Scripting via tracked search_params","severity":"medium","cvss":5.4,"cwe":["CWE-79"],"vendor":"sveltejs","product":"@sveltejs/kit","ecosystem":"npm","affected":["@sveltejs/kit >= 2.0.0, < 2.20.6"],"patched":["@sveltejs/kit 2.20.6"],"published":"2025-04-14","updated":"2026-10-18","sourceUpdated":"2026-10-18T15:04:06Z","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-6q87-84jw-cjhp","references":[{"url":"https://github.com/sveltejs/kit/security/advisories/GHSA-6q87-84jw-cjhp"},{"url":"https://github.com/sveltejs/kit/commit/d3300c6a67908590266c363dba7b0835d9a194cf"},{"url":"https://github.com/sveltejs/kit/releases/tag/%40sveltejs%2Fkit%402.20.6"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-32388"},{"url":"https://github.com/advisories/GHSA-6q87-84jw-cjhp"}],"tags":["ghsa","npm"],"epss":0.00304,"epssPercentile":0.21769,"ingestedAt":"2026-10-18T15:45:12.223Z","slug":"CVE-2025-32388","body":"## Overview\n\n### Summary\n\nUnsanitized search param names cause XSS vulnerability. You are affected if you iterate over all entries of `event.url.searchParams` inside a server `load` function. Attackers can exploit it by crafting a malicious URL and getting a user to click a link with said URL.\n\n### Details\n\nSvelteKit tracks which parameters in `event.url.searchParams` are read inside server `load` functions. If the application iterates over the these parameters, the `uses.search_params` array included in the boot script (embedded in the server-rendered HTML) will have any search param name included in unsanitized form.\n\n`packages/kit/src/runtime/server/utils.js:150` has the `stringify_uses(node)` function which prints these out.\n\n### Reproduction\n\nIn a `+page.server.js` or `+layout.server.js`:\n\n```js\n/** @type {import('@sveltejs/kit').Load} */\nexport function load(event) {\n  const values = {};\n\n  for (const key of event.url.searchParams.keys()) {\n    values[key] = event.url.searchParams.get(key);\n  }\n}\n```\n\nIf a user visits the page in question via a link containing `?</script/><script>window.pwned%3D1</script/>`, the `</script>` will be included verbatim in the payload, causing the embedded script to be executed.\n\nIt is not necessary to return the parameter value from `load` or render it in the page, only to read it (which causes it to be tracked as a dependency) while `load` is running.\n\n### Impact\n\nAny application that iterates over all values in `event.url.searchParams` in a `load` function in `+page.server.js` or `+layout.server.js` (directly or indirectly) is vulnerable to XSS.\n\n## Affected packages\n\n- `@sveltejs/kit >= 2.0.0, < 2.20.6`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `@sveltejs/kit 2.20.6`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":29.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}