{
  "document": {
    "acknowledgments": [
      {
        "names": [
          "Tobias Johansson with \u003ca href=\"https://www.crayon.com/\"\u003eCrayon\u003c/a\u003e"
        ]
      },
      {
        "names": [
          "Kevin with Crayon"
        ]
      }
    ],
    "aggregate_severity": {
      "namespace": "https://www.microsoft.com/en-us/msrc/security-update-severity-rating-system",
      "text": "Important"
    },
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      },
      {
        "category": "general",
        "text": "Required. The vulnerability documented by this CVE requires customer action to resolve.",
        "title": "Customer Action"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2023-21809 Microsoft Defender for Endpoint Security Feature Bypass Vulnerability - HTML",
        "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21809"
      },
      {
        "category": "self",
        "summary": "CVE-2023-21809 Microsoft Defender for Endpoint Security Feature Bypass Vulnerability - CSAF",
        "url": "https://msrc.microsoft.com/csaf/2023/msrc_cve-2023-21809.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Exploitability Index",
        "url": "https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "Microsoft Defender for Endpoint Security Feature Bypass Vulnerability",
    "tracking": {
      "current_release_date": "2023-02-21T08:00:00.000Z",
      "generator": {
        "date": "2025-01-01T00:40:39.924Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2023-21809",
      "initial_release_date": "2023-02-14T08:00:00.000Z",
      "revision_history": [
        {
          "date": "2023-02-14T08:00:00.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        },
        {
          "date": "2023-02-21T08:00:00.000Z",
          "legacy_version": "1.1",
          "number": "2",
          "summary": "Added FAQ information. This is an informational change only."
        }
      ],
      "status": "final",
      "version": "2"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "category": "product_version_range",
            "name": "\u003c1.379.200.0",
            "product": {
              "name": "Microsoft Defender Security Intelligence Updates \u003c1.379.200.0",
              "product_id": "1"
            }
          },
          {
            "category": "product_version",
            "name": "1.379.200.0",
            "product": {
              "name": "Microsoft Defender Security Intelligence Updates 1.379.200.0",
              "product_id": "12162"
            }
          }
        ],
        "category": "product_name",
        "name": "Microsoft Defender Security Intelligence Updates"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2023-21809",
      "notes": [
        {
          "category": "general",
          "text": "Microsoft",
          "title": "Assigning CNA"
        },
        {
          "category": "faq",
          "text": "A user needs to be tricked into running malicious files.",
          "title": "According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?"
        },
        {
          "category": "faq",
          "text": "An attacker who successfully exploited this vulnerability could bypass the Windows Defender Attack Surface Reduction blocking feature.",
          "title": "What kind of security feature could be bypassed by successfully exploiting this vulnerability?"
        },
        {
          "category": "faq",
          "text": "This vulnerability existed in the Defender Security Intelligence Updates and not the Malware protection engine.  The version of the signatures that addressed the vulnerability is 1.379.200.0 and was updated automatically. Check the current version in Windows Update history Definition Updates to see the most recently installed definitions.",
          "title": "How can I check if I\u0027m protected from this vulnerability?"
        }
      ],
      "product_status": {
        "fixed": [
          "12162"
        ],
        "known_affected": [
          "1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2023-21809 Microsoft Defender for Endpoint Security Feature Bypass Vulnerability - HTML",
          "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21809"
        },
        {
          "category": "self",
          "summary": "CVE-2023-21809 Microsoft Defender for Endpoint Security Feature Bypass Vulnerability - CSAF",
          "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21809"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2023-02-14T08:00:00.000Z",
          "details": "1.379.200.0:Security Update:https://learn.microsoft.com/en-us/microsoft-365/security/defender-endpoint/manage-updates-baselines-microsoft-defender-antivirus?view=o365-worldwide#security-intelligence-updates",
          "product_ids": [
            "1"
          ],
          "url": "https://learn.microsoft.com/en-us/microsoft-365/security/defender-endpoint/manage-updates-baselines-microsoft-defender-antivirus?view=o365-worldwide#security-intelligence-updates"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "environmentalsScore": 0.0,
            "exploitCodeMaturity": "UNPROVEN",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "remediationLevel": "OFFICIAL_FIX",
            "reportConfidence": "CONFIRMED",
            "scope": "UNCHANGED",
            "temporalScore": 6.8,
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "1"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Security Feature Bypass"
        },
        {
          "category": "exploit_status",
          "details": "Exploited:No;Latest Software Release:Exploitation Less Likely"
        }
      ],
      "title": "Microsoft Defender for Endpoint Security Feature Bypass Vulnerability"
    }
  ]
}