{
  "crds_version": "0.1",
  "kind": "base",
  "id": "crds:cve-2021-22681",
  "revision": 1,
  "title": "Rockwell Studio 5000 — recoverable key trusted by Logix controllers",
  "summary": "Rockwell's Studio 5000 Logix Designer 21 and later, and RSLogix 5000 versions 16 to 20, hold the key their controllers use to tell genuine design software apart. Anyone who recovers it can connect an unauthorised application to a Logix controller.",
  "source_type": "cve",
  "severity": "critical",
  "cvss": {
    "score": 9.8,
    "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
    "version": "3.1"
  },
  "epss": 0.6363,
  "exploitation": {
    "known_exploited": true,
    "exploit_available": false,
    "attack_complexity": "low",
    "kev_added": "2026-03-05",
    "prerequisites": "Network access to the controller, plus the key recovered out of the design software."
  },
  "mitre_attack": [
    "T1552"
  ],
  "kill_chain": "credential_access",
  "recommended_action": "Follow CISA advisory ICSA-21-056-03 now; keep Logix controllers on a segmented network and restrict which stations may open a controller connection at all.",
  "confidence": "high",
  "provenance": [
    {
      "fields": [
        "cvss",
        "exploitation.attack_complexity",
        "exploitation.exploit_available",
        "references",
        "published_at"
      ],
      "source": "https://nvd.nist.gov/vuln/detail/CVE-2021-22681",
      "retrieved_at": "2026-09-24T08:51:39.744Z",
      "confidence": "high",
      "extractor": "scrty-crds-pipeline/0.1"
    },
    {
      "fields": [
        "exploitation.known_exploited",
        "exploitation.kev_added"
      ],
      "source": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "retrieved_at": "2026-09-24T08:51:39.744Z",
      "confidence": "high",
      "extractor": "scrty-crds-pipeline/0.1"
    },
    {
      "fields": [
        "epss"
      ],
      "source": "https://api.first.org/data/v1/epss?cve=CVE-2021-22681",
      "retrieved_at": "2026-09-24T08:51:39.744Z",
      "confidence": "high",
      "extractor": "scrty-crds-pipeline/0.1"
    },
    {
      "fields": [
        "title",
        "summary",
        "severity",
        "remediation",
        "mitre_attack",
        "kill_chain",
        "recommended_action",
        "confidence",
        "tags",
        "exploitation.prerequisites"
      ],
      "source": "https://nvd.nist.gov/vuln/detail/CVE-2021-22681",
      "retrieved_at": "2026-09-24T08:51:39.744Z",
      "confidence": "high",
      "extractor": "claude-code"
    }
  ],
  "references": [
    {
      "type": "cve",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-22681",
      "label": "NVD record"
    },
    {
      "type": "cisa",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "label": "CISA Known Exploited Vulnerabilities catalog"
    },
    {
      "type": "writeup",
      "url": "https://us-cert.cisa.gov/ics/advisories/icsa-21-056-03"
    }
  ],
  "published_at": "2021-03-03T18:15:14.643Z",
  "issued_at": "2026-09-24T08:51:39.744Z",
  "tags": [
    "rockwell",
    "logix",
    "ics",
    "ot",
    "hardcoded-key",
    "kev"
  ]
}