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ubuntu-cve-2019-9517
Vulnerability from osv_ubuntu
Published
2019-08-13 00:00
Modified
2026-04-22 07:38
Summary
Details

Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service. The attacker opens the HTTP/2 window so the peer can send without constraint; however, they leave the TCP window closed so the peer cannot actually write (many of) the bytes on the wire. The attacker then sends a stream of requests for a large response object. Depending on how the servers queue the responses, this can consume excess memory, CPU, or both.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5 (High)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5 (High)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "apache2",
            "binary_version": "2.4.29-1ubuntu4.10"
          },
          {
            "binary_name": "apache2-bin",
            "binary_version": "2.4.29-1ubuntu4.10"
          },
          {
            "binary_name": "apache2-data",
            "binary_version": "2.4.29-1ubuntu4.10"
          },
          {
            "binary_name": "apache2-suexec-custom",
            "binary_version": "2.4.29-1ubuntu4.10"
          },
          {
            "binary_name": "apache2-suexec-pristine",
            "binary_version": "2.4.29-1ubuntu4.10"
          },
          {
            "binary_name": "apache2-utils",
            "binary_version": "2.4.29-1ubuntu4.10"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "apache2",
        "purl": "pkg:deb/ubuntu/apache2@2.4.29-1ubuntu4.10?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.29-1ubuntu4.10"
            }
          ],
          "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"
      ]
    }
  ],
  "aliases": [],
  "details": "Some HTTP/2 implementations are vulnerable to unconstrained interal data buffering, potentially leading to a denial of service. The attacker opens the HTTP/2 window so the peer can send without constraint; however, they leave the TCP window closed so the peer cannot actually write (many of) the bytes on the wire. The attacker then sends a stream of requests for a large response object. Depending on how the servers queue the responses, this can consume excess memory, CPU, or both.",
  "id": "UBUNTU-CVE-2019-9517",
  "modified": "2026-04-22T07:38:56Z",
  "published": "2019-08-13T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2019-9517"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/Netflix/security-bulletins/blob/master/advisories/third-party/2019-002.md"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4113-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2019-9517"
    }
  ],
  "related": [
    "USN-4113-1"
  ],
  "schema_version": "1.7.0",
  "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": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2019-9517"
  ]
}



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