{"cve":"CVE-2026-46625","nvd":{"published":"2026-06-10T22:16:59.613","modified":"2026-09-09T13:20:18.357","status":"Modified","description":"JavaScript Cookie is a JavaScript API for handling cookies, client-side. Prior to version 3.0.7, js-cookie's internal assign() helper copies properties with for...in + plain assignment. When the source object is produced by JSON.parse, the JSON object's \"__proto__\" member is an own enumerable property, so the for…in enumerates it and the target[key] = source[key] write triggers the Object.prototype.__proto__ setter on the fresh target ({}). The result is a per-instance prototype hijack: Object.prototype itself is untouched, but the merged attributes object now inherits attacker-controlled keys. Because the consuming set() function then enumerates the merged object with another for...in, every key the attacker placed on the polluted prototype lands in the resulting Set-Cookie string as an attribute pair. The attacker can set domain=, secure=, samesite=, expires=, and path= on cookies whose attributes the developer thought were locked down. This issue has been patched in version 3.0.7.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":["CWE-1321","CWE-915"],"references":["https://github.com/js-cookie/js-cookie/commit/eb3c40e89731e99b8970faaf35ddad249c6c0020","https://github.com/js-cookie/js-cookie/releases/tag/v3.0.7","https://github.com/js-cookie/js-cookie/security/advisories/GHSA-qjx8-664m-686j","https://access.redhat.com/errata/RHSA-2026:33183","https://access.redhat.com/errata/RHSA-2026:36625"],"products":["js-cookie:javascript_cookie","redhat:3scale_api_management","redhat:ansible_automation_platform","redhat:enterprise_linux","redhat:openshift_ai","redhat:openshift_lightspeed"],"source":"nvd","synced_at":"2026-10-19T22:38:48.522727527+00:00"},"epss":{"cve":"CVE-2026-46625","score":0.00919,"percentile":0.60273,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-qjx8-664m-686j","url":"https://osv.dev/vulnerability/GHSA-qjx8-664m-686j","summary":"JavaScript Cookie: Per-instance prototype hijack in assign() enables cookie-attribute injection","modified":"2026-09-10T03:50:47.374021767Z","packages":[{"ecosystem":"npm","name":"js-cookie","purl":"pkg:npm/js-cookie","ranges":["<3.0.7"],"fixed":["3.0.7"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}