Debug-Prototype-Pollution-Check-V2

The model receives the prompt (and optional system message). The run uses scorer rubric_json_metrics with the JSON configuration below. Pass/fail and partial credit are determined entirely by that scorer against the model output; no human grading.

Return JSON only with keys diagnosis, fix, tests. A permissions check calls obj.hasOwnProperty('admin') directly on an untrusted user-supplied object; an attacker supplies an object whose __proto__ overrides hasOwnProperty to always return true, bypassing the check. Identify the prototype pollution vector and fix it.

{
  "metrics": {
    "repro": {
      "checks": [
        {
          "contains": [
            "hasOwnProperty"
          ]
        },
        {
          "contains": [
            "__proto__"
          ]
        },
        {
          "contains": [
            "untrusted"
          ]
        },
        {
          "contains": [
            "bypass"
          ]
        }
      ]
    },
    "hidden": {
      "checks": [
        {
          "contains": [
            "Object.prototype.hasOwnProperty.call"
          ]
        },
        {
          "contains": [
            "Object.hasOwn"
          ]
        },
        {
          "contains": [
            "null prototype"
          ]
        }
      ]
    },
    "diagnose": {
      "checks": [
        {
          "contains": [
            "prototype pollution"
          ]
        },
        {
          "contains": [
            "poisoned prototype"
          ]
        },
        {
          "contains": [
            "unsafe hasOwnProperty"
          ]
        }
      ]
    }
  }
}