{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@openzeppelin/contracts-upgradeable"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.1.0"
            },
            {
              "fixed": "4.3.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": true,
    "github_reviewed_at": "2021-09-14T22:17:40Z",
    "nvd_published_at": null,
    "severity": "CRITICAL"
  },
  "details": "### Impact\n\nUpgradeable contracts using `UUPSUpgradeable` may be vulnerable to an attack affecting uninitialized implementation contracts. We will update this advisory with more information soon.\n\n### Patches\n\nA fix is included in version 4.3.2 of `@openzeppelin/contracts` and `@openzeppelin/contracts-upgradeable`.\n\n### Workarounds\n\nInitialize implementation contracts using `UUPSUpgradeable` by invoking the initializer function (usually called `initialize`). An example is provided [in the forum](https://forum.openzeppelin.com/t/security-advisory-initialize-uups-implementation-contracts/15301).\n\n### References\n\nA post-mortem will be published in a few days in the [OpenZeppelin Forum](https://forum.openzeppelin.com/).\n\n### For more information\n\nIf you have any questions or comments about this advisory, or need assistance executing the mitigation, email us at security@openzeppelin.com.",
  "id": "GHSA-q4h9-46xg-m3x9",
  "modified": "2021-09-14T22:17:40Z",
  "published": "2021-09-15T20:22:13Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/OpenZeppelin/openzeppelin-contracts-upgradeable/security/advisories/GHSA-q4h9-46xg-m3x9"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/OpenZeppelin/openzeppelin-contracts-upgradeable"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [],
  "summary": "UUPSUpgradeable vulnerability in @openzeppelin/contracts-upgradeable"
}