{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "5.0.45"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "28b3c03c63bdbff53115fdaa46c56980e7942acc"
            },
            {
              "fixed": "6cb38594f88c47562f8f96f70a5492f3b6bd0ba8"
            }
          ],
          "repo": "https://github.com/feathersjs/feathers",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-28xv-ph75-77wh"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-1321"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54335.json"
  },
  "details": "Feathersjs is a framework for creating web APIs and real-time applications with TypeScript or JavaScript. In 5.0.44 and earlier, the _.merge(target, source) utility exported by @feathersjs/commons recursively merges source into target by iterating Object.keys(source). When source was produced by JSON.parse and contains a __proto__, constructor, or prototype key, that key is returned as an own-enumerable property; the recursive merge then resolves target['__proto__'] to Object.prototype and writes attacker-supplied properties onto it, polluting the prototype for all plain objects in the process for the lifetime of the Node process. This issue is fixed in version 5.0.45.",
  "id": "CVE-2026-54335",
  "modified": "2026-07-22T05:30:11.846399812Z",
  "published": "2026-07-17T20:56:51.857Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/feathersjs/feathers/releases/tag/v5.0.45"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54335.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/feathersjs/feathers/security/advisories/GHSA-28xv-ph75-77wh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54335"
    },
    {
      "type": "FIX",
      "url": "https://github.com/feathersjs/feathers/commit/28b3c03c63bdbff53115fdaa46c56980e7942acc"
    },
    {
      "type": "FIX",
      "url": "https://github.com/feathersjs/feathers/pull/3690"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Feathersjs: Prototype pollution in @feathersjs/commons _.merge via JSON-parsed __proto__"
}