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ubuntu-cve-2026-2229
Vulnerability from osv_ubuntu
Published
2026-03-12 21:16
Modified
2026-06-30 16:18
Summary
Details

ImpactThe undici WebSocket client is vulnerable to a denial-of-service attack due to improper validation of the server_max_window_bits parameter in the permessage-deflate extension. When a WebSocket client connects to a server, it automatically advertises support for permessage-deflate compression. A malicious server can respond with an out-of-range server_max_window_bits value (outside zlib's valid range of 8-15). When the server subsequently sends a compressed frame, the client attempts to create a zlib InflateRaw instance with the invalid windowBits value, causing a synchronous RangeError exception that is not caught, resulting in immediate process termination. The vulnerability exists because: * The isValidClientWindowBits() function only validates that the value contains ASCII digits, not that it falls within the valid range 8-15 * The createInflateRaw() call is not wrapped in a try-catch block * The resulting exception propagates up through the call stack and crashes the Node.js process

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:3.1/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": {
        "binaries": [
          {
            "binary_name": "node-llhttp",
            "binary_version": "9.1.3~5.26.3+dfsg1+~cs23.10.12-2"
          },
          {
            "binary_name": "node-undici",
            "binary_version": "5.26.3+dfsg1+~cs23.10.12-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "node-undici",
        "purl": "pkg:deb/ubuntu/node-undici@5.26.3+dfsg1+~cs23.10.12-2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.22.1+dfsg1+~cs20.10.10.2-1ubuntu1",
        "5.26.3+dfsg1+~cs23.10.12-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libllhttp9.2",
            "binary_version": "9.2.1~7.3.0+dfsg1+~cs24.12.11-2"
          },
          {
            "binary_name": "node-llhttp",
            "binary_version": "9.2.1~7.3.0+dfsg1+~cs24.12.11-2"
          },
          {
            "binary_name": "node-undici",
            "binary_version": "7.3.0+dfsg1+~cs24.12.11-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "node-undici",
        "purl": "pkg:deb/ubuntu/node-undici@7.3.0+dfsg1+~cs24.12.11-2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "7.3.0+dfsg1+~cs24.12.11-1",
        "7.3.0+dfsg1+~cs24.12.11-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "node-undici",
            "binary_version": "7.18.2+dfsg+~cs3.2.0-1build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "node-undici",
        "purl": "pkg:deb/ubuntu/node-undici@7.18.2+dfsg+~cs3.2.0-1build1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "7.3.0+dfsg1+~cs24.12.11-2",
        "7.16.0+dfsg+~cs3.2.0-2",
        "7.18.2+dfsg+~cs3.2.0-1",
        "7.18.2+dfsg+~cs3.2.0-1build1"
      ]
    }
  ],
  "aliases": [],
  "details": "ImpactThe undici WebSocket client is vulnerable to a denial-of-service attack due to improper validation of the\u00a0server_max_window_bits\u00a0parameter in the permessage-deflate extension. When a WebSocket client connects to a server, it automatically advertises support for permessage-deflate compression. A malicious server can respond with an out-of-range\u00a0server_max_window_bits\u00a0value (outside zlib\u0027s valid range of 8-15). When the server subsequently sends a compressed frame, the client attempts to create a zlib InflateRaw instance with the invalid windowBits value, causing a synchronous RangeError exception that is not caught, resulting in immediate process termination. The vulnerability exists because:   *  The\u00a0isValidClientWindowBits()\u00a0function only validates that the value contains ASCII digits, not that it falls within the valid range 8-15   *  The\u00a0createInflateRaw()\u00a0call is not wrapped in a try-catch block   *  The resulting exception propagates up through the call stack and crashes the Node.js process",
  "id": "UBUNTU-CVE-2026-2229",
  "modified": "2026-06-30T16:18:32Z",
  "published": "2026-03-12T21:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-2229"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-2229"
    }
  ],
  "related": [],
  "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:3.1/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-2026-2229"
  ]
}



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