{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "3.0.7"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "eb3c40e89731e99b8970faaf35ddad249c6c0020"
            },
            {
              "fixed": "17bacba0171dd022728d8fdeba3203c60791bf58"
            }
          ],
          "repo": "https://github.com/js-cookie/js-cookie",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-qjx8-664m-686j"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-1321"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46625.json"
  },
  "details": "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.",
  "id": "CVE-2026-46625",
  "modified": "2026-07-10T03:53:44.404479177Z",
  "published": "2026-06-10T21:18:05.372Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/js-cookie/js-cookie/releases/tag/v3.0.7"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46625.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:33183"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:36625"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/security/cve/CVE-2026-46625"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46625.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/js-cookie/js-cookie/security/advisories/GHSA-qjx8-664m-686j"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46625"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2487740"
    },
    {
      "type": "FIX",
      "url": "https://github.com/js-cookie/js-cookie/commit/eb3c40e89731e99b8970faaf35ddad249c6c0020"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "JavaScript Cookie: Per-instance prototype hijack in assign() enables cookie-attribute injection"
}