{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2021-27395",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-27395",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2021-10-12T09:49:20.000Z",
    "updatedAt": "2024-08-03T20:48:16.821Z",
    "importedAt": "2026-10-24T01:56:26.894Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": null,
      "summary": "A vulnerability has been identified in SIMATIC Process Historian 2013 and earlier (All versions), SIMATIC Process Historian 2014 (All versions < SP3 Update 6), SIMATIC Process Historian 2019 (All versions), SIMATIC Process Historian 2020 (All versions). An interface in the software that is used for critical functionalities lacks authentication, which could allow a malicious user to maliciously insert, modify or delete data.",
      "affected": [
        {
          "vendor": "Siemens",
          "product": "SIMATIC Process Historian 2013 and earlier",
          "versions": [
            {
              "version": "All versions",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Siemens",
          "product": "SIMATIC Process Historian 2014",
          "versions": [
            {
              "version": "All versions < SP3 Update 6",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Siemens",
          "product": "SIMATIC Process Historian 2019",
          "versions": [
            {
              "version": "All versions",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Siemens",
          "product": "SIMATIC Process Historian 2020",
          "versions": [
            {
              "version": "All versions",
              "status": "affected"
            }
          ]
        }
      ]
    }
  }
}