usn-4994-1
Vulnerability from osv_ubuntu
Published
2021-06-21 14:01
Modified
2026-04-22 07:36
Summary
apache2 vulnerabilities
Details

Marc Stern discovered that the Apache mod_proxy_http module incorrectly handled certain requests. A remote attacker could possibly use this issue to cause Apache to crash, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04. (CVE-2020-13950)

Antonio Morales discovered that the Apache mod_auth_digest module incorrectly handled certain Digest nonces. A remote attacker could possibly use this issue to cause Apache to crash, resulting in a denial of service. (CVE-2020-35452)

Antonio Morales discovered that the Apache mod_session module incorrectly handled certain Cookie headers. A remote attacker could possibly use this issue to cause Apache to crash, resulting in a denial of service. (CVE-2021-26690)

Christophe Jaillet discovered that the Apache mod_session module incorrectly handled certain SessionHeader values. A remote attacker could use this issue to cause Apache to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-26691)

Christoph Anton Mitterer discovered that the new MergeSlashes configuration option resulted in unexpected behaviour in certain situations. (CVE-2021-30641)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2020-35452",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-26690",
              "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-2021-26691",
              "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"
                }
              ]
            },
            {
              "id": "CVE-2021-30641",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:18.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "apache2",
            "binary_version": "2.4.29-1ubuntu4.16"
          },
          {
            "binary_name": "apache2-bin",
            "binary_version": "2.4.29-1ubuntu4.16"
          },
          {
            "binary_name": "apache2-data",
            "binary_version": "2.4.29-1ubuntu4.16"
          },
          {
            "binary_name": "apache2-suexec-custom",
            "binary_version": "2.4.29-1ubuntu4.16"
          },
          {
            "binary_name": "apache2-suexec-pristine",
            "binary_version": "2.4.29-1ubuntu4.16"
          },
          {
            "binary_name": "apache2-utils",
            "binary_version": "2.4.29-1ubuntu4.16"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.29-1ubuntu4.16?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.29-1ubuntu4.16"
            }
          ],
          "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"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2020-13950",
              "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": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2020-35452",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-26690",
              "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-2021-26691",
              "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"
                }
              ]
            },
            {
              "id": "CVE-2021-30641",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:20.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "apache2",
            "binary_version": "2.4.41-4ubuntu3.3"
          },
          {
            "binary_name": "apache2-bin",
            "binary_version": "2.4.41-4ubuntu3.3"
          },
          {
            "binary_name": "apache2-data",
            "binary_version": "2.4.41-4ubuntu3.3"
          },
          {
            "binary_name": "apache2-suexec-custom",
            "binary_version": "2.4.41-4ubuntu3.3"
          },
          {
            "binary_name": "apache2-suexec-pristine",
            "binary_version": "2.4.41-4ubuntu3.3"
          },
          {
            "binary_name": "apache2-utils",
            "binary_version": "2.4.41-4ubuntu3.3"
          },
          {
            "binary_name": "libapache2-mod-md",
            "binary_version": "2.4.41-4ubuntu3.3"
          },
          {
            "binary_name": "libapache2-mod-proxy-uwsgi",
            "binary_version": "2.4.41-4ubuntu3.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.41-4ubuntu3.3?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.41-4ubuntu3.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.41-1ubuntu1",
        "2.4.41-4ubuntu1",
        "2.4.41-4ubuntu2",
        "2.4.41-4ubuntu3",
        "2.4.41-4ubuntu3.1"
      ]
    }
  ],
  "aliases": [],
  "details": "Marc Stern discovered that the Apache mod_proxy_http module incorrectly\nhandled certain requests. A remote attacker could possibly use this issue\nto cause Apache to crash, resulting in a denial of service. This issue only\naffected Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04. (CVE-2020-13950)\n\nAntonio Morales discovered that the Apache mod_auth_digest module\nincorrectly handled certain Digest nonces. A remote attacker could possibly\nuse this issue to cause Apache to crash, resulting in a denial of service.\n(CVE-2020-35452)\n\nAntonio Morales discovered that the Apache mod_session module incorrectly\nhandled certain Cookie headers. A remote attacker could possibly use this\nissue to cause Apache to crash, resulting in a denial of service.\n(CVE-2021-26690)\n\nChristophe Jaillet discovered that the Apache mod_session module\nincorrectly handled certain SessionHeader values. A remote attacker could\nuse this issue to cause Apache to crash, resulting in a denial of service,\nor possibly execute arbitrary code. (CVE-2021-26691)\n\nChristoph Anton Mitterer discovered that the new MergeSlashes configuration\noption resulted in unexpected behaviour in certain situations.\n(CVE-2021-30641)\n",
  "id": "USN-4994-1",
  "modified": "2026-04-22T07:36:59Z",
  "published": "2021-06-21T14:01:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4994-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2020-13950"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2020-35452"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-26690"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-26691"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-30641"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "apache2 vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2020-13950",
    "UBUNTU-CVE-2020-35452",
    "UBUNTU-CVE-2021-26690",
    "UBUNTU-CVE-2021-26691",
    "UBUNTU-CVE-2021-30641"
  ]
}



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