OESA-2021-1246 (CVE-2021-26691)

Vulnerability from osv_openeuler – Published: 2021-06-26 11:04 – Updated: 2026-08-06 11:04 – Source website
VLAI
Summary
httpd security update
Details

Apache HTTP Server is a powerful and flexible HTTP/1.1 compliant web server.

Security Fix(es):

In Apache HTTP Server versions 2.4.0 to 2.4.46 a specially crafted SessionHeader sent by an origin server could cause a heap overflow(CVE-2021-26691)

Apache HTTP Server versions 2.4.41 to 2.4.46 mod_proxy_http can be made to crash (NULL pointer dereference) with specially crafted requests using both Content-Length and Transfer-Encoding headers, leading to a Denial of Service(CVE-2020-13950)

Apache HTTP Server versions 2.4.0 to 2.4.46 A specially crafted Digest nonce can cause a stack overflow in mod_auth_digest. There is no report of this overflow being exploitable, nor the Apache HTTP Server team could create one, though some particular compiler and/or compilation option might make it possible, with limited consequences anyway due to the size (a single byte) and the value (zero byte) of the overflow(CVE-2020-35452)

Apache HTTP Server versions 2.4.39 to 2.4.46 Unexpected matching behavior with MergeSlashes OFF(CVE-2021-30641)

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "mod_ssl-2.4.43-7.oe1.aarch64.rpm",
          "mod_md-2.4.43-7.oe1.aarch64.rpm",
          "httpd-devel-2.4.43-7.oe1.aarch64.rpm",
          "httpd-2.4.43-7.oe1.aarch64.rpm",
          "httpd-tools-2.4.43-7.oe1.aarch64.rpm",
          "httpd-debugsource-2.4.43-7.oe1.aarch64.rpm",
          "httpd-debuginfo-2.4.43-7.oe1.aarch64.rpm",
          "mod_ldap-2.4.43-7.oe1.aarch64.rpm",
          "mod_session-2.4.43-7.oe1.aarch64.rpm",
          "mod_proxy_html-2.4.43-7.oe1.aarch64.rpm"
        ],
        "noarch": [
          "httpd-help-2.4.43-7.oe1.noarch.rpm",
          "httpd-filesystem-2.4.43-7.oe1.noarch.rpm"
        ],
        "src": [
          "httpd-2.4.43-7.oe1.src.rpm"
        ],
        "x86_64": [
          "mod_session-2.4.43-7.oe1.x86_64.rpm",
          "httpd-tools-2.4.43-7.oe1.x86_64.rpm",
          "mod_md-2.4.43-7.oe1.x86_64.rpm",
          "httpd-2.4.43-7.oe1.x86_64.rpm",
          "httpd-debuginfo-2.4.43-7.oe1.x86_64.rpm",
          "httpd-debugsource-2.4.43-7.oe1.x86_64.rpm",
          "mod_ldap-2.4.43-7.oe1.x86_64.rpm",
          "mod_ssl-2.4.43-7.oe1.x86_64.rpm",
          "mod_proxy_html-2.4.43-7.oe1.x86_64.rpm",
          "httpd-devel-2.4.43-7.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP1",
        "name": "httpd",
        "purl": "pkg:rpm/openEuler/httpd\u0026distro=openEuler-20.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.43-7.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "Apache HTTP Server is a powerful and flexible HTTP/1.1 compliant web server.\r\n\r\nSecurity Fix(es):\r\n\r\nIn Apache HTTP Server versions 2.4.0 to 2.4.46 a specially crafted SessionHeader sent by an origin server could cause a heap overflow(CVE-2021-26691)\r\n\r\nApache HTTP Server versions 2.4.41 to 2.4.46 mod_proxy_http can be made to crash (NULL pointer dereference) with specially crafted requests using both Content-Length and Transfer-Encoding headers, leading to a Denial of Service(CVE-2020-13950)\r\n\r\nApache HTTP Server versions 2.4.0 to 2.4.46 A specially crafted Digest nonce can cause a stack overflow in mod_auth_digest. There is no report of this overflow being exploitable, nor the Apache HTTP Server team could create one, though some particular compiler and/or compilation option might make it possible, with limited consequences anyway due to the size (a single byte) and the value (zero byte) of the overflow(CVE-2020-35452)\n\nApache HTTP Server versions 2.4.39 to 2.4.46 Unexpected matching behavior with MergeSlashes OFF(CVE-2021-30641)",
  "id": "OESA-2021-1246",
  "modified": "2026-08-06T11:04:29Z",
  "published": "2021-06-26T11:04:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2021-1246"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-26691"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-13950"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-35452"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-30641"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "httpd security update",
  "upstream": [
    "CVE-2021-26691",
    "CVE-2020-13950",
    "CVE-2020-35452",
    "CVE-2021-30641"
  ]
}



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