usn-4994-2
Vulnerability from osv_ubuntu
Published
2021-06-21 15:25
Modified
2026-06-29 10:52
Summary
apache2 vulnerabilities
Details

USN-4994-1 fixed several vulnerabilities in Apache. This update provides the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.

Original advisory details:

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: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+esm1"
          },
          {
            "binary_name": "apache2-bin",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-data",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-mpm-event",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-mpm-itk",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-mpm-prefork",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-mpm-worker",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-suexec",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-suexec-custom",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-suexec-pristine",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2-utils",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "apache2.2-bin",
            "binary_version": "2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "libapache2-mod-macro",
            "binary_version": "1:2.4.7-1ubuntu4.22+esm1"
          },
          {
            "binary_name": "libapache2-mod-proxy-html",
            "binary_version": "1:2.4.7-1ubuntu4.22+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.7-1ubuntu4.22+esm1?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.7-1ubuntu4.22+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.6-2ubuntu2",
        "2.4.6-2ubuntu3",
        "2.4.6-2ubuntu4",
        "2.4.7-1ubuntu1",
        "2.4.7-1ubuntu2",
        "2.4.7-1ubuntu3",
        "2.4.7-1ubuntu4",
        "2.4.7-1ubuntu4.1",
        "2.4.7-1ubuntu4.4",
        "2.4.7-1ubuntu4.5",
        "2.4.7-1ubuntu4.6",
        "2.4.7-1ubuntu4.7",
        "2.4.7-1ubuntu4.8",
        "2.4.7-1ubuntu4.9",
        "2.4.7-1ubuntu4.10",
        "2.4.7-1ubuntu4.11",
        "2.4.7-1ubuntu4.13",
        "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"
      ]
    },
    {
      "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: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+esm1"
          },
          {
            "binary_name": "apache2-bin",
            "binary_version": "2.4.18-2ubuntu3.17+esm1"
          },
          {
            "binary_name": "apache2-data",
            "binary_version": "2.4.18-2ubuntu3.17+esm1"
          },
          {
            "binary_name": "apache2-suexec-custom",
            "binary_version": "2.4.18-2ubuntu3.17+esm1"
          },
          {
            "binary_name": "apache2-suexec-pristine",
            "binary_version": "2.4.18-2ubuntu3.17+esm1"
          },
          {
            "binary_name": "apache2-utils",
            "binary_version": "2.4.18-2ubuntu3.17+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.18-2ubuntu3.17+esm1?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.18-2ubuntu3.17+esm1"
            }
          ],
          "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",
        "2.4.18-2ubuntu3.3",
        "2.4.18-2ubuntu3.4",
        "2.4.18-2ubuntu3.5",
        "2.4.18-2ubuntu3.7",
        "2.4.18-2ubuntu3.8",
        "2.4.18-2ubuntu3.9",
        "2.4.18-2ubuntu3.10",
        "2.4.18-2ubuntu3.12",
        "2.4.18-2ubuntu3.13",
        "2.4.18-2ubuntu3.14",
        "2.4.18-2ubuntu3.15",
        "2.4.18-2ubuntu3.17"
      ]
    }
  ],
  "aliases": [],
  "details": "USN-4994-1 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 Antonio Morales discovered that the Apache mod_auth_digest module\n incorrectly handled certain Digest nonces. A remote attacker could possibly\n use this issue to cause Apache to crash, resulting in a denial of service.\n (CVE-2020-35452)\n\n Antonio Morales discovered that the Apache mod_session module incorrectly\n handled certain Cookie headers. A remote attacker could possibly use this\n issue to cause Apache to crash, resulting in a denial of service.\n (CVE-2021-26690)\n\n Christophe Jaillet discovered that the Apache mod_session module\n incorrectly handled certain SessionHeader values. A remote attacker could\n use this issue to cause Apache to crash, resulting in a denial of service,\n or possibly execute arbitrary code. (CVE-2021-26691)\n\n Christoph Anton Mitterer discovered that the new MergeSlashes configuration\n option resulted in unexpected behaviour in certain situations.\n (CVE-2021-30641)\n",
  "id": "USN-4994-2",
  "modified": "2026-06-29T10:52:50Z",
  "published": "2021-06-21T15:25:05Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4994-2"
    },
    {
      "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-2020-35452",
    "UBUNTU-CVE-2021-26690",
    "UBUNTU-CVE-2021-26691",
    "UBUNTU-CVE-2021-30641"
  ]
}



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