{"id":"CVE-2026-82257","aliases":["EUVD-2026-67583","GHSA-6mgf-42wv-8j7p","GHSA-866w-xmhq-wj7x"],"status":"published","title":"SvelteKit before 2.69.1 Prototype Pollution via File Input","description":"SvelteKit versions before 2.69.1 contain a prototype pollution vulnerability in remote form functions with file input fields that accept arbitrary user-controlled path names. Attackers can manipulate the deletion path to remove methods on the prototype, potentially disabling application functionality.","severity":{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00358,"percentile":0.29884,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-1321"],"published":"2026-07-24T15:58:05Z","modified":"2026-10-28T02:30:39Z","fixes":[{"ecosystem":"npm","package":"@sveltejs/kit","fixed_in":["2.69.1"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"@sveltejs/kit","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"2.69.0"},{"fixed":"2.69.1"}]}]},{"source":"osv","ecosystem":"npm","package":"@sveltejs/kit","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.69.1"}]}]}],"products":[{"vendor":"svelte","product":"sveltekit"},{"vendor":"sveltejs","product":"kit"}],"references":[{"url":"https://github.com/sveltejs/kit/security/advisories/GHSA-866w-xmhq-wj7x","tags":["vendor-advisory","Vendor Advisory","advisory","web"]},{"url":"https://www.vulncheck.com/advisories/sveltekit-before-2.69.1-prototype-pollution-via-file-input","tags":["third-party-advisory","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-82257","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-6mgf-42wv-8j7p"},{"url":"https://github.com/sveltejs/kit/pull/16218","tags":["web"]},{"url":"https://github.com/sveltejs/kit/commit/df32f6fe86cdd0b68b650e3e4631e5896453dcd3","tags":["web"]},{"url":"https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@2.69.1","tags":["web"]},{"url":"https://github.com/sveltejs/kit/releases/tag/@sveltejs/kit@3.0.0-next.7","tags":["web"]},{"url":"https://github.com/advisories/GHSA-866w-xmhq-wj7x"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82257.json","tags":["advisory"]},{"url":"https://github.com/sveltejs/kit","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-82257","title":"SvelteKit before 2.69.1 Prototype Pollution via File Input","description":"SvelteKit versions before 2.69.1 contain a prototype pollution vulnerability in remote form functions with file input fields that accept arbitrary user-controlled path names. Attackers can manipulate the deletion path to remove methods on the prototype, potentially disabling application functionality.","status":"published","published":"2026-08-28T10:49:41.355Z","modified":"2026-10-08T15:25:29.825Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T13:40:46.161838Z"}],"euvd":[{"id":"EUVD-2026-67583","description":"SvelteKit versions before 2.69.1 contain a prototype pollution vulnerability in remote form functions with file input fields that accept arbitrary user-controlled path names. Attackers can manipulate the deletion path to remove methods on the prototype, potentially disabling application functionality.","status":"published","published":"2026-08-28T10:49:41Z","modified":"2026-10-08T15:25:29Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T17:27:28.564399Z"}],"ghsa":[{"id":"GHSA-6mgf-42wv-8j7p","title":"SvelteKit versions before 2.69.1 contain a prototype pollution vulnerability in remote form...","description":"SvelteKit versions before 2.69.1 contain a prototype pollution vulnerability in remote form functions with file input fields that accept arbitrary user-controlled path names. Attackers can manipulate the deletion path to remove methods on the prototype, potentially disabling application functionality.","status":"published","published":"2026-08-28T12:30:29Z","modified":"2026-08-28T12:30:29Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T15:11:06.970333Z"},{"id":"GHSA-866w-xmhq-wj7x","title":"SvelteKit: Prototype pollution in file input deletion path in remote-function forms","description":"If you use remote form functions, have an input field of type `file`, and accept arbitrary user-controlled path names for the field, then you are vulnerable to a prototype pollution attack where the attacker can remove e.g. methods on the prototype.","status":"published","published":"2026-07-24T15:58:05Z","modified":"2026-07-24T15:58:07Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T14:40:52.46233Z"}],"nvd":[{"id":"CVE-2026-82257","description":"SvelteKit versions before 2.69.1 contain a prototype pollution vulnerability in remote form functions with file input fields that accept arbitrary user-controlled path names. 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Attackers can manipulate the deletion path to remove methods on the prototype, potentially disabling application functionality.","status":"published","published":"2026-08-28T10:49:41.355Z","modified":"2026-10-28T02:30:39.034934412Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T15:45:18.131258Z"},{"id":"GHSA-866w-xmhq-wj7x","title":"SvelteKit: Prototype pollution in file input deletion path in remote-function forms","description":"If you use remote form functions, have an input field of type `file`, and accept arbitrary user-controlled path names for the field, then you are vulnerable to a prototype pollution attack where the attacker can remove e.g. methods on the prototype.","status":"published","published":"2026-07-24T15:58:05Z","modified":"2026-08-29T03:55:36.205388747Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-1321"],"updated_at":"2026-11-02T15:46:41.732368Z"}]}}