USN-5090-2 (UBUNTU-CVE-2021-34798)

Vulnerability from osv_ubuntu – Published: 2021-09-27 16:46 – Updated: 2026-06-29 10:52 – Source website
VLAI
Summary
apache2 vulnerabilities
Details

USN-5090-1 fixed several vulnerabilities in Apache. This update provides the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.

Original advisory details:

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)

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-2021-34798",
              "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:Pro:14.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "apache2",
            "binary_version": "2.4.7-1ubuntu4.22+esm2"
          },
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          },
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          },
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            "binary_version": "2.4.7-1ubuntu4.22+esm2"
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            "binary_version": "2.4.7-1ubuntu4.22+esm2"
          },
          {
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            "binary_version": "2.4.7-1ubuntu4.22+esm2"
          },
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            "binary_version": "2.4.7-1ubuntu4.22+esm2"
          },
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          },
          {
            "binary_name": "libapache2-mod-macro",
            "binary_version": "1:2.4.7-1ubuntu4.22+esm2"
          },
          {
            "binary_name": "libapache2-mod-proxy-html",
            "binary_version": "1:2.4.7-1ubuntu4.22+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.7-1ubuntu4.22+esm2?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
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            },
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            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.6-2ubuntu2",
        "2.4.6-2ubuntu3",
        "2.4.6-2ubuntu4",
        "2.4.7-1ubuntu1",
        "2.4.7-1ubuntu2",
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        "2.4.7-1ubuntu4.15",
        "2.4.7-1ubuntu4.16",
        "2.4.7-1ubuntu4.17",
        "2.4.7-1ubuntu4.18",
        "2.4.7-1ubuntu4.19",
        "2.4.7-1ubuntu4.20",
        "2.4.7-1ubuntu4.21",
        "2.4.7-1ubuntu4.22",
        "2.4.7-1ubuntu4.22+esm1"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "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:Pro:16.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "apache2",
            "binary_version": "2.4.18-2ubuntu3.17+esm2"
          },
          {
            "binary_name": "apache2-bin",
            "binary_version": "2.4.18-2ubuntu3.17+esm2"
          },
          {
            "binary_name": "apache2-data",
            "binary_version": "2.4.18-2ubuntu3.17+esm2"
          },
          {
            "binary_name": "apache2-suexec-custom",
            "binary_version": "2.4.18-2ubuntu3.17+esm2"
          },
          {
            "binary_name": "apache2-suexec-pristine",
            "binary_version": "2.4.18-2ubuntu3.17+esm2"
          },
          {
            "binary_name": "apache2-utils",
            "binary_version": "2.4.18-2ubuntu3.17+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.18-2ubuntu3.17+esm2?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.18-2ubuntu3.17+esm2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.12-2ubuntu2",
        "2.4.17-1ubuntu1",
        "2.4.17-2ubuntu1",
        "2.4.17-3ubuntu1",
        "2.4.18-1ubuntu1",
        "2.4.18-2ubuntu1",
        "2.4.18-2ubuntu2",
        "2.4.18-2ubuntu3",
        "2.4.18-2ubuntu3.1",
        "2.4.18-2ubuntu3.2",
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        "2.4.18-2ubuntu3.5",
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        "2.4.18-2ubuntu3.17",
        "2.4.18-2ubuntu3.17+esm1"
      ]
    }
  ],
  "aliases": [],
  "details": "USN-5090-1 fixed several vulnerabilities in Apache. This update provides\nthe corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.\n\nOriginal advisory details:\n\n It was discovered that the Apache HTTP Server incorrectly handled certain\n malformed requests. A remote attacker could possibly use this issue to\n cause the server to crash, resulting in a denial of service.\n (CVE-2021-34798)\n\n It was discovered that the Apache HTTP Server incorrectly handled escaping\n quotes. If the server was configured with third-party modules, a remote\n attacker could use this issue to cause the server to crash, resulting in a\n denial of service, or possibly execute arbitrary code. (CVE-2021-39275)\n\n It was discovered that the Apache mod_proxy module incorrectly handled\n certain request uri-paths. A remote attacker could possibly use this issue\n to cause the server to forward requests to arbitrary origin servers.\n (CVE-2021-40438)\n",
  "id": "USN-5090-2",
  "modified": "2026-06-29T10:52:51Z",
  "published": "2021-09-27T16:46:11Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5090-2"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-34798"
    },
    {
      "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-2021-34798",
    "UBUNTU-CVE-2021-39275",
    "UBUNTU-CVE-2021-40438"
  ]
}



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