{
  "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-2023-3138 A vulnerability was found in libX11. The security flaw occurs because the functions in src/InitExt.c in libX11 do not check that the values provided for the Request Event or Error IDs are within the bounds of the arrays that those functions write to using those IDs as array indexes. They trust that they were called with values provided by an Xserver adhering to the bounds specified in the X11 protocol as all X servers provided by X.Org do. As the protocol only specifies a single byte for these values an out-of-bounds value provided by a malicious server (or a malicious proxy-in-the-middle) can only overwrite other portions of the Display structure and not write outside the bounds of the Display structure itself possibly causing the client to crash with this memory corruption. - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2023/msrc_cve-2023-3138.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": "A vulnerability was found in libX11. The security flaw occurs because the functions in src/InitExt.c in libX11 do not check that the values provided for the Request Event or Error IDs are within the bounds of the arrays that those functions write to using those IDs as array indexes. They trust that they were called with values provided by an Xserver adhering to the bounds specified in the X11 protocol as all X servers provided by X.Org do. As the protocol only specifies a single byte for these values an out-of-bounds value provided by a malicious server (or a malicious proxy-in-the-middle) can only overwrite other portions of the Display structure and not write outside the bounds of the Display structure itself possibly causing the client to crash with this memory corruption.",
    "tracking": {
      "current_release_date": "2023-06-29T00:00:00.000Z",
      "generator": {
        "date": "2025-10-20T00:29:44.630Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2023-3138",
      "initial_release_date": "2023-06-01T07:00:00.000Z",
      "revision_history": [
        {
          "date": "2023-06-29T00:00:00.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "2.0",
                "product": {
                  "name": "CBL Mariner 2.0",
                  "product_id": "17086"
                }
              }
            ],
            "category": "product_name",
            "name": "Azure Linux"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003ccbl2 libX11 1.6.12-6",
                "product": {
                  "name": "\u003ccbl2 libX11 1.6.12-6",
                  "product_id": "1"
                }
              },
              {
                "category": "product_version",
                "name": "cbl2 libX11 1.6.12-6",
                "product": {
                  "name": "cbl2 libX11 1.6.12-6",
                  "product_id": "18350"
                }
              }
            ],
            "category": "product_name",
            "name": "libX11"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ],
    "relationships": [
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "\u003ccbl2 libX11 1.6.12-6 as a component of CBL Mariner 2.0",
          "product_id": "17086-1"
        },
        "product_reference": "1",
        "relates_to_product_reference": "17086"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "cbl2 libX11 1.6.12-6 as a component of CBL Mariner 2.0",
          "product_id": "18350-17086"
        },
        "product_reference": "18350",
        "relates_to_product_reference": "17086"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2023-3138",
      "cwe": {
        "id": "CWE-787",
        "name": "Out-of-bounds Write"
      },
      "notes": [
        {
          "category": "general",
          "text": "redhat",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "fixed": [
          "18350-17086"
        ],
        "known_affected": [
          "17086-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2023-3138 A vulnerability was found in libX11. The security flaw occurs because the functions in src/InitExt.c in libX11 do not check that the values provided for the Request Event or Error IDs are within the bounds of the arrays that those functions write to using those IDs as array indexes. They trust that they were called with values provided by an Xserver adhering to the bounds specified in the X11 protocol as all X servers provided by X.Org do. As the protocol only specifies a single byte for these values an out-of-bounds value provided by a malicious server (or a malicious proxy-in-the-middle) can only overwrite other portions of the Display structure and not write outside the bounds of the Display structure itself possibly causing the client to crash with this memory corruption. - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2023/msrc_cve-2023-3138.json"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2023-06-29T00:00:00.000Z",
          "details": "1.6.12-6:Security Update:https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade",
          "product_ids": [
            "17086-1"
          ],
          "url": "https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "environmentalsScore": 0.0,
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "temporalScore": 7.5,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "products": [
            "17086-1"
          ]
        }
      ],
      "title": "A vulnerability was found in libX11. The security flaw occurs because the functions in src/InitExt.c in libX11 do not check that the values provided for the Request Event or Error IDs are within the bounds of the arrays that those functions write to using those IDs as array indexes. They trust that they were called with values provided by an Xserver adhering to the bounds specified in the X11 protocol as all X servers provided by X.Org do. As the protocol only specifies a single byte for these values an out-of-bounds value provided by a malicious server (or a malicious proxy-in-the-middle) can only overwrite other portions of the Display structure and not write outside the bounds of the Display structure itself possibly causing the client to crash with this memory corruption."
    }
  ]
}