{
  "id": "CVE-2021-27852",
  "url": "https://spydr.io/cve/CVE-2021-27852",
  "published": "2021-05-27T21:15:20.567Z",
  "modified": "2026-06-17T03:45:31.033Z",
  "score": 9.8,
  "severity": "critical",
  "cvss_version": "3.1",
  "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
  "score_source": "NVD",
  "epss": 0.30258,
  "epss_percentile": 0.98184,
  "exploited": true,
  "kev": {
    "added": "2022-04-11",
    "due": "2022-05-02",
    "action": "Versions 6 and earlier for this product are end-of-life and must be removed from agency networks. Versions 7 and later are not considered vulnerable.",
    "ransomware": "Unknown",
    "name": "Checkbox Survey Deserialization of Untrusted Data Vulnerability",
    "notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-27852"
  },
  "ssvc_exploitation": "active",
  "vendors": [
    "Checkbox"
  ],
  "products": [
    "Checkbox Survey"
  ],
  "cwes": [
    "CWE-502"
  ],
  "description": "Deserialization of Untrusted Data vulnerability in CheckboxWeb.dll of Checkbox Survey allows an unauthenticated remote attacker to execute arbitrary code. This issue affects: Checkbox Survey versions prior to 7.",
  "status": "Analyzed",
  "score_type": "Primary",
  "scores": {
    "cvss_v40": null,
    "cvss_v31": 9.8,
    "cvss_v30": null
  },
  "references": [
    {
      "url": "https://www.kb.cert.org/vuls/id/706695",
      "tags": [
        "Third Party Advisory",
        "US Government Resource"
      ]
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27852",
      "tags": [
        "US Government Resource"
      ]
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2021-27852",
  "covered_in": [],
  "attribution": [
    {
      "source": "NVD",
      "url": "https://nvd.nist.gov",
      "notice": "This product uses data from the NVD API but is not endorsed or certified by the NVD."
    },
    {
      "source": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "notice": "Known exploited vulnerabilities from the CISA KEV catalog."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss",
      "notice": "Exploit prediction scores from FIRST EPSS."
    }
  ]
}