{
  "document": {
    "category": "csaf_vex",
    "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"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2021-3738 In DCE/RPC it is possible to share the handles (cookies for resource state) between multiple connections via a mechanism called \u0027association groups\u0027. These handles can reference connections to our sam.ldb database. However while the database was correctly shared the user credentials state was only pointed at and when one connection within that association group ended the database would be left pointing at an invalid \u0027struct session_info\u0027. The most likely outcome here is a crash but it is possible that the use-after-free could instead allow different user state to be pointed at and this might allow more privileged access. - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2022/msrc_cve-2021-3738.json"
      },
      {
        "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": "In DCE/RPC it is possible to share the handles (cookies for resource state) between multiple connections via a mechanism called \u0027association groups\u0027. These handles can reference connections to our sam.ldb database. However while the database was correctly shared the user credentials state was only pointed at and when one connection within that association group ended the database would be left pointing at an invalid \u0027struct session_info\u0027. The most likely outcome here is a crash but it is possible that the use-after-free could instead allow different user state to be pointed at and this might allow more privileged access.",
    "tracking": {
      "current_release_date": "2024-10-15T00:00:00.000Z",
      "generator": {
        "date": "2025-10-19T23:23:33.140Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2021-3738",
      "initial_release_date": "2022-03-02T00:00:00.000Z",
      "revision_history": [
        {
          "date": "2024-10-15T00:00:00.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
              }
            ],
            "category": "product_name",
            "name": "Azure Linux"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003cazl3 samba 4.18.3-1",
                "product": {
                  "name": "\u003cazl3 samba 4.18.3-1",
                  "product_id": "1"
                }
              },
              {
                "category": "product_version",
                "name": "azl3 samba 4.18.3-1",
                "product": {
                  "name": "azl3 samba 4.18.3-1",
                  "product_id": "16864"
                }
              }
            ],
            "category": "product_name",
            "name": "samba"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ],
    "relationships": [
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "\u003cazl3 samba 4.18.3-1 as a component of Azure Linux 3.0",
          "product_id": "17084-1"
        },
        "product_reference": "1",
        "relates_to_product_reference": "17084"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "azl3 samba 4.18.3-1 as a component of Azure Linux 3.0",
          "product_id": "16864-17084"
        },
        "product_reference": "16864",
        "relates_to_product_reference": "17084"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2021-3738",
      "cwe": {
        "id": "CWE-416",
        "name": "Use After Free"
      },
      "notes": [
        {
          "category": "general",
          "text": "redhat",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "fixed": [
          "16864-17084"
        ],
        "known_affected": [
          "17084-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2021-3738 In DCE/RPC it is possible to share the handles (cookies for resource state) between multiple connections via a mechanism called \u0027association groups\u0027. These handles can reference connections to our sam.ldb database. However while the database was correctly shared the user credentials state was only pointed at and when one connection within that association group ended the database would be left pointing at an invalid \u0027struct session_info\u0027. The most likely outcome here is a crash but it is possible that the use-after-free could instead allow different user state to be pointed at and this might allow more privileged access. - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2022/msrc_cve-2021-3738.json"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2024-10-15T00:00:00.000Z",
          "details": "4.18.3-1:Security Update:https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade",
          "product_ids": [
            "17084-1"
          ],
          "url": "https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "environmentalsScore": 0.0,
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "temporalScore": 8.8,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "products": [
            "17084-1"
          ]
        }
      ],
      "title": "In DCE/RPC it is possible to share the handles (cookies for resource state) between multiple connections via a mechanism called \u0027association groups\u0027. These handles can reference connections to our sam.ldb database. However while the database was correctly shared the user credentials state was only pointed at and when one connection within that association group ended the database would be left pointing at an invalid \u0027struct session_info\u0027. The most likely outcome here is a crash but it is possible that the use-after-free could instead allow different user state to be pointed at and this might allow more privileged access."
    }
  ]
}