USN-5090-1 (UBUNTU-CVE-2021-33193)

Vulnerability from osv_ubuntu – Published: 2021-09-27 14:06 – Updated: 2026-04-22 07:37 – Source website
VLAI
Summary
apache2 vulnerabilities
Details

James Kettle discovered that the Apache HTTP Server HTTP/2 module incorrectly handled certain crafted methods. A remote attacker could possibly use this issue to perform request splitting or cache poisoning attacks. (CVE-2021-33193)

It was discovered that the Apache HTTP Server incorrectly handled certain malformed requests. A remote attacker could possibly use this issue to cause the server to crash, resulting in a denial of service. (CVE-2021-34798)

Li Zhi Xin discovered that the Apache mod_proxy_uwsgi module incorrectly handled certain request uri-paths. A remote attacker could possibly use this issue to cause the server to crash, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS and Ubuntu 21.04. (CVE-2021-36160)

It was discovered that the Apache HTTP Server incorrectly handled escaping quotes. If the server was configured with third-party modules, a remote attacker could use this issue to cause the server to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-39275)

It was discovered that the Apache mod_proxy module incorrectly handled certain request uri-paths. A remote attacker could possibly use this issue to cause the server to forward requests to arbitrary origin servers. (CVE-2021-40438)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-33193",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-34798",
              "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": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-39275",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:18.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "apache2",
            "binary_version": "2.4.29-1ubuntu4.17"
          },
          {
            "binary_name": "apache2-bin",
            "binary_version": "2.4.29-1ubuntu4.17"
          },
          {
            "binary_name": "apache2-data",
            "binary_version": "2.4.29-1ubuntu4.17"
          },
          {
            "binary_name": "apache2-suexec-custom",
            "binary_version": "2.4.29-1ubuntu4.17"
          },
          {
            "binary_name": "apache2-suexec-pristine",
            "binary_version": "2.4.29-1ubuntu4.17"
          },
          {
            "binary_name": "apache2-utils",
            "binary_version": "2.4.29-1ubuntu4.17"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.29-1ubuntu4.17?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.29-1ubuntu4.17"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.27-2ubuntu3",
        "2.4.29-1ubuntu1",
        "2.4.29-1ubuntu2",
        "2.4.29-1ubuntu3",
        "2.4.29-1ubuntu4",
        "2.4.29-1ubuntu4.1",
        "2.4.29-1ubuntu4.2",
        "2.4.29-1ubuntu4.3",
        "2.4.29-1ubuntu4.4",
        "2.4.29-1ubuntu4.5",
        "2.4.29-1ubuntu4.6",
        "2.4.29-1ubuntu4.7",
        "2.4.29-1ubuntu4.8",
        "2.4.29-1ubuntu4.10",
        "2.4.29-1ubuntu4.11",
        "2.4.29-1ubuntu4.12",
        "2.4.29-1ubuntu4.13",
        "2.4.29-1ubuntu4.14",
        "2.4.29-1ubuntu4.16"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-33193",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-34798",
              "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": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-36160",
              "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": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-39275",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:20.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "apache2",
            "binary_version": "2.4.41-4ubuntu3.5"
          },
          {
            "binary_name": "apache2-bin",
            "binary_version": "2.4.41-4ubuntu3.5"
          },
          {
            "binary_name": "apache2-data",
            "binary_version": "2.4.41-4ubuntu3.5"
          },
          {
            "binary_name": "apache2-suexec-custom",
            "binary_version": "2.4.41-4ubuntu3.5"
          },
          {
            "binary_name": "apache2-suexec-pristine",
            "binary_version": "2.4.41-4ubuntu3.5"
          },
          {
            "binary_name": "apache2-utils",
            "binary_version": "2.4.41-4ubuntu3.5"
          },
          {
            "binary_name": "libapache2-mod-md",
            "binary_version": "2.4.41-4ubuntu3.5"
          },
          {
            "binary_name": "libapache2-mod-proxy-uwsgi",
            "binary_version": "2.4.41-4ubuntu3.5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.41-4ubuntu3.5?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.41-4ubuntu3.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.41-1ubuntu1",
        "2.4.41-4ubuntu1",
        "2.4.41-4ubuntu2",
        "2.4.41-4ubuntu3",
        "2.4.41-4ubuntu3.1",
        "2.4.41-4ubuntu3.3",
        "2.4.41-4ubuntu3.4"
      ]
    }
  ],
  "aliases": [],
  "details": "James Kettle discovered that the Apache HTTP Server HTTP/2 module\nincorrectly handled certain crafted methods. A remote attacker could\npossibly use this issue to perform request splitting or cache poisoning\nattacks. (CVE-2021-33193)\n\nIt was discovered that the Apache HTTP Server incorrectly handled certain\nmalformed requests. A remote attacker could possibly use this issue to\ncause the server to crash, resulting in a denial of service.\n(CVE-2021-34798)\n\nLi Zhi Xin discovered that the Apache mod_proxy_uwsgi module incorrectly\nhandled certain request uri-paths. A remote attacker could possibly use\nthis issue to cause the server to crash, resulting in a denial of service.\nThis issue only affected Ubuntu 20.04 LTS and Ubuntu 21.04.\n(CVE-2021-36160)\n\nIt was discovered that the Apache HTTP Server incorrectly handled escaping\nquotes. If the server was configured with third-party modules, a remote\nattacker could use this issue to cause the server to crash, resulting in a\ndenial of service, or possibly execute arbitrary code. (CVE-2021-39275)\n\nIt was discovered that the Apache mod_proxy module incorrectly handled\ncertain request uri-paths. A remote attacker could possibly use this issue\nto cause the server to forward requests to arbitrary origin servers.\n(CVE-2021-40438)\n",
  "id": "USN-5090-1",
  "modified": "2026-04-22T07:37:00Z",
  "published": "2021-09-27T14:06:45Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5090-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-33193"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-34798"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-36160"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-39275"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-40438"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "apache2 vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2021-33193",
    "UBUNTU-CVE-2021-34798",
    "UBUNTU-CVE-2021-36160",
    "UBUNTU-CVE-2021-39275",
    "UBUNTU-CVE-2021-40438"
  ]
}



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