{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 5.9.2"
      },
      "package": {
        "ecosystem": "npm",
        "name": "devalue"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.9.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-1321"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-10-01T15:13:23Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "This is another instance of https://github.com/sveltejs/devalue/security/advisories/GHSA-mwv9-gp5h-frr4, where some payloads could cause `parse` to create objects with a `__proto__` own property. This on its own is not enough to cause prototype pollution, and indeed this is actually how `JSON.parse` works, but we decided to be a little more defensive here and not allow the creation of objects with `__proto__` own-properties. It is very unlikely for this to cause any issues.",
  "id": "GHSA-4q55-j62x-fr9h",
  "modified": "2026-10-01T15:13:23Z",
  "published": "2026-10-01T15:13:23Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/sveltejs/devalue/security/advisories/GHSA-4q55-j62x-fr9h"
    },
    {
      "type": "WEB",
      "url": "https://github.com/sveltejs/devalue/commit/9ec513072e31f45e60d44dad6f0dba9c92bb8675"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/sveltejs/devalue"
    },
    {
      "type": "WEB",
      "url": "https://github.com/sveltejs/devalue/releases/tag/v5.9.3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "devalue: Malformed null-prototype object keys bypass __proto__ rejection via property-key coercion"
}