usn-4991-1
Vulnerability from osv_ubuntu
Published
2021-06-17 14:59
Modified
2026-06-29 10:52
Summary
libxml2 vulnerabilities
Details

Yunho Kim discovered that libxml2 incorrectly handled certain error conditions. A remote attacker could exploit this with a crafted XML file to cause a denial of service, or possibly cause libxml2 to expose sensitive information. This issue only affected Ubuntu 14.04 ESM, and Ubuntu 16.04 ESM. (CVE-2017-8872)

Zhipeng Xie discovered that libxml2 incorrectly handled certain XML schemas. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 14.04 ESM, Ubuntu 16.04 ESM, and Ubuntu 18.04 LTS. (CVE-2019-20388)

It was discovered that libxml2 incorrectly handled invalid UTF-8 input. A remote attacker could possibly exploit this with a crafted XML file to cause libxml2 to crash, resulting in a denial of service. This issue only affected Ubuntu 14.04 ESM, Ubuntu 16.04 ESM, Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu 20.10. (CVE-2020-24977)

It was discovered that libxml2 incorrectly handled invalid UTF-8 input. A remote attacker could possibly exploit this with a crafted XML file to cause libxml2 to crash, resulting in a denial of service. (CVE-2021-3517)

It was discovered that libxml2 did not properly handle certain crafted XML files. A local attacker could exploit this with a crafted input to cause libxml2 to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-3516, CVE-2021-3518)

It was discovered that libxml2 incorrectly handled error states. A remote attacker could exploit this with a crafted XML file to cause libxml2 to crash, resulting in a denial of service. (CVE-2021-3537)

Sebastian Pipping discovered that libxml2 did not properly handle certain crafted XML files. A remote attacker could exploit this with a crafted XML file to cause libxml2 to crash, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04. (CVE-2021-3541)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2017-8872",
              "severity": [
                {
                  "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2019-20388",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2020-24977",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3516",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3517",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3518",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3537",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:14.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libxml2",
            "binary_version": "2.9.1+dfsg1-3ubuntu4.13+esm2"
          },
          {
            "binary_name": "libxml2-utils",
            "binary_version": "2.9.1+dfsg1-3ubuntu4.13+esm2"
          },
          {
            "binary_name": "python-libxml2",
            "binary_version": "2.9.1+dfsg1-3ubuntu4.13+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "libxml2",
        "purl": "pkg:deb/ubuntu/libxml2@2.9.1+dfsg1-3ubuntu4.13+esm2?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.9.1+dfsg1-3ubuntu4.13+esm2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.9.1+dfsg1-3ubuntu2",
        "2.9.1+dfsg1-3ubuntu3",
        "2.9.1+dfsg1-3ubuntu4",
        "2.9.1+dfsg1-3ubuntu4.1",
        "2.9.1+dfsg1-3ubuntu4.2",
        "2.9.1+dfsg1-3ubuntu4.3",
        "2.9.1+dfsg1-3ubuntu4.4",
        "2.9.1+dfsg1-3ubuntu4.5",
        "2.9.1+dfsg1-3ubuntu4.6",
        "2.9.1+dfsg1-3ubuntu4.7",
        "2.9.1+dfsg1-3ubuntu4.8",
        "2.9.1+dfsg1-3ubuntu4.9",
        "2.9.1+dfsg1-3ubuntu4.10",
        "2.9.1+dfsg1-3ubuntu4.11",
        "2.9.1+dfsg1-3ubuntu4.12",
        "2.9.1+dfsg1-3ubuntu4.13",
        "2.9.1+dfsg1-3ubuntu4.13+esm1"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2017-8872",
              "severity": [
                {
                  "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2019-20388",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2020-24977",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3516",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3517",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3518",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3537",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:16.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libxml2",
            "binary_version": "2.9.3+dfsg1-1ubuntu0.7+esm1"
          },
          {
            "binary_name": "libxml2-utils",
            "binary_version": "2.9.3+dfsg1-1ubuntu0.7+esm1"
          },
          {
            "binary_name": "python-libxml2",
            "binary_version": "2.9.3+dfsg1-1ubuntu0.7+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "libxml2",
        "purl": "pkg:deb/ubuntu/libxml2@2.9.3+dfsg1-1ubuntu0.7+esm1?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.9.3+dfsg1-1ubuntu0.7+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.9.2+zdfsg1-4",
        "2.9.2+zdfsg1-4ubuntu1",
        "2.9.2+zdfsg1-4ubuntu2",
        "2.9.2+zdfsg1-4ubuntu3",
        "2.9.3+dfsg1-1",
        "2.9.3+dfsg1-1ubuntu0.1",
        "2.9.3+dfsg1-1ubuntu0.2",
        "2.9.3+dfsg1-1ubuntu0.3",
        "2.9.3+dfsg1-1ubuntu0.4",
        "2.9.3+dfsg1-1ubuntu0.5",
        "2.9.3+dfsg1-1ubuntu0.6",
        "2.9.3+dfsg1-1ubuntu0.7"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2019-20388",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2020-24977",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3516",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3517",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3518",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3537",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:18.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libxml2",
            "binary_version": "2.9.4+dfsg1-6.1ubuntu1.4"
          },
          {
            "binary_name": "libxml2-utils",
            "binary_version": "2.9.4+dfsg1-6.1ubuntu1.4"
          },
          {
            "binary_name": "python-libxml2",
            "binary_version": "2.9.4+dfsg1-6.1ubuntu1.4"
          },
          {
            "binary_name": "python3-libxml2",
            "binary_version": "2.9.4+dfsg1-6.1ubuntu1.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "libxml2",
        "purl": "pkg:deb/ubuntu/libxml2@2.9.4+dfsg1-6.1ubuntu1.4?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.9.4+dfsg1-6.1ubuntu1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.9.4+dfsg1-4ubuntu1",
        "2.9.4+dfsg1-5ubuntu1",
        "2.9.4+dfsg1-5ubuntu2",
        "2.9.4+dfsg1-5.1ubuntu1",
        "2.9.4+dfsg1-5.2ubuntu1",
        "2.9.4+dfsg1-6.1ubuntu1",
        "2.9.4+dfsg1-6.1ubuntu1.2",
        "2.9.4+dfsg1-6.1ubuntu1.3"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2020-24977",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3516",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3517",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3518",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3537",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-3541",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:20.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libxml2",
            "binary_version": "2.9.10+dfsg-5ubuntu0.20.04.1"
          },
          {
            "binary_name": "libxml2-utils",
            "binary_version": "2.9.10+dfsg-5ubuntu0.20.04.1"
          },
          {
            "binary_name": "python-libxml2",
            "binary_version": "2.9.10+dfsg-5ubuntu0.20.04.1"
          },
          {
            "binary_name": "python3-libxml2",
            "binary_version": "2.9.10+dfsg-5ubuntu0.20.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "libxml2",
        "purl": "pkg:deb/ubuntu/libxml2@2.9.10+dfsg-5ubuntu0.20.04.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.9.10+dfsg-5ubuntu0.20.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.9.4+dfsg1-7ubuntu3",
        "2.9.4+dfsg1-7ubuntu5",
        "2.9.4+dfsg1-8ubuntu1",
        "2.9.4+dfsg1-8ubuntu2",
        "2.9.4+dfsg1-8ubuntu3",
        "2.9.10+dfsg-1ubuntu3",
        "2.9.10+dfsg-4build1",
        "2.9.10+dfsg-5"
      ]
    }
  ],
  "aliases": [],
  "details": "Yunho Kim discovered that libxml2 incorrectly handled certain error\nconditions. A remote attacker could exploit this with a crafted XML file to\ncause a denial of service, or possibly cause libxml2 to expose sensitive\ninformation. This issue only affected Ubuntu 14.04 ESM, and Ubuntu 16.04\nESM. (CVE-2017-8872)\n\nZhipeng Xie discovered that libxml2 incorrectly handled certain XML\nschemas. A remote attacker could possibly use this issue to cause a denial\nof service. This issue only affected Ubuntu 14.04 ESM, Ubuntu 16.04 ESM,\nand Ubuntu 18.04 LTS. (CVE-2019-20388)\n\nIt was discovered that libxml2 incorrectly handled invalid UTF-8 input. A\nremote attacker could possibly exploit this with a crafted XML file to\ncause libxml2 to crash, resulting in a denial of service. This issue only\naffected Ubuntu 14.04 ESM, Ubuntu 16.04 ESM, Ubuntu 18.04 LTS, Ubuntu 20.04\nLTS and Ubuntu 20.10. (CVE-2020-24977)\n\nIt was discovered that libxml2 incorrectly handled invalid UTF-8 input. A\nremote attacker could possibly exploit this with a crafted XML file to\ncause libxml2 to crash, resulting in a denial of service. (CVE-2021-3517)\n\nIt was discovered that libxml2 did not properly handle certain crafted XML\nfiles. A local attacker could exploit this with a crafted input to cause\nlibxml2 to crash, resulting in a denial of service, or possibly execute\narbitrary code. (CVE-2021-3516, CVE-2021-3518)\n\nIt was discovered that libxml2 incorrectly handled error states. A remote\nattacker could exploit this with a crafted XML file to cause libxml2 to\ncrash, resulting in a denial of service. (CVE-2021-3537)\n\nSebastian Pipping discovered that libxml2 did not properly handle certain\ncrafted XML files. A remote attacker could exploit this with a crafted XML\nfile to cause libxml2 to crash, resulting in a denial of service. This\nissue only affected Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04.\n(CVE-2021-3541)\n",
  "id": "USN-4991-1",
  "modified": "2026-06-29T10:52:50Z",
  "published": "2021-06-17T14:59:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4991-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2017-8872"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2019-20388"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2020-24977"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-3516"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-3517"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-3518"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-3537"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-3541"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "libxml2 vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2017-8872",
    "UBUNTU-CVE-2019-20388",
    "UBUNTU-CVE-2020-24977",
    "UBUNTU-CVE-2021-3516",
    "UBUNTU-CVE-2021-3517",
    "UBUNTU-CVE-2021-3518",
    "UBUNTU-CVE-2021-3537",
    "UBUNTU-CVE-2021-3541"
  ]
}



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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.