UBUNTU-CVE-2025-26466 (CVE-2025-26466)

Vulnerability from osv_ubuntu – Published: 2025-02-18 00:00 – Updated: 2025-09-08 17:08 – Source website
VLAI
Details

A flaw was found in the OpenSSH package. For each ping packet the SSH server receives, a pong packet is allocated in a memory buffer and stored in a queue of packages. It is only freed when the server/client key exchange has finished. A malicious client may keep sending such packages, leading to an uncontrolled increase in memory consumption on the server side. Consequently, the server may become unavailable, resulting in a denial of service attack.

Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/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": "openssh-client",
            "binary_version": "1:9.6p1-3ubuntu13.8"
          },
          {
            "binary_name": "openssh-server",
            "binary_version": "1:9.6p1-3ubuntu13.8"
          },
          {
            "binary_name": "openssh-sftp-server",
            "binary_version": "1:9.6p1-3ubuntu13.8"
          },
          {
            "binary_name": "openssh-tests",
            "binary_version": "1:9.6p1-3ubuntu13.8"
          },
          {
            "binary_name": "ssh",
            "binary_version": "1:9.6p1-3ubuntu13.8"
          },
          {
            "binary_name": "ssh-askpass-gnome",
            "binary_version": "1:9.6p1-3ubuntu13.8"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "openssh",
        "purl": "pkg:deb/ubuntu/openssh@1:9.6p1-3ubuntu13.8?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:9.6p1-3ubuntu13.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:9.3p1-1ubuntu3",
        "1:9.4p1-1ubuntu1",
        "1:9.6p1-3ubuntu1",
        "1:9.6p1-3ubuntu2",
        "1:9.6p1-3ubuntu11",
        "1:9.6p1-3ubuntu12",
        "1:9.6p1-3ubuntu13",
        "1:9.6p1-3ubuntu13.3",
        "1:9.6p1-3ubuntu13.4",
        "1:9.6p1-3ubuntu13.5",
        "1:9.6p1-3ubuntu13.7"
      ]
    }
  ],
  "aliases": [],
  "details": "A flaw was found in the OpenSSH package. For each ping packet the SSH server receives, a pong packet is allocated in a memory buffer and stored in a queue of packages. It is only freed when the server/client key exchange has finished. A malicious client may keep sending such packages, leading to an uncontrolled increase in memory consumption on the server side. Consequently, the server may become unavailable, resulting in a denial of service attack.",
  "id": "UBUNTU-CVE-2025-26466",
  "modified": "2025-09-08T17:08:12Z",
  "published": "2025-02-18T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2025-26466"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-26466"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-7270-1"
    }
  ],
  "related": [
    "USN-7270-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2025-26466"
  ]
}



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