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UBUNTU-CVE-2021-21409 (CVE-2021-21409)

Vulnerability from osv_ubuntu – Published: 2021-03-30 15:15 – Updated: 2026-06-08 16:09 – Source website
VLAI
Details

Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before version 4.1.61.Final there is a vulnerability that enables request smuggling. The content-length header is not correctly validated if the request only uses a single Http2HeaderFrame with the endStream set to to true. This could lead to request smuggling if the request is proxied to a remote peer and translated to HTTP/1.1. This is a followup of GHSA-wm47-8v5p-wjpj/CVE-2021-21295 which did miss to fix this one case. This was fixed as part of 4.1.61.Final.

Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libnetty-java",
            "binary_version": "1:3.2.6.Final-2+deb8u2ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "netty",
        "purl": "pkg:deb/ubuntu/netty@1:3.2.6.Final-2+deb8u2ubuntu0.1~esm1?arch=source\u0026distro=esm-infra-legacy/trusty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:3.2.6.Final-2",
        "1:3.2.6.Final-2+deb8u2build0.14.04.1~esm1",
        "1:3.2.6.Final-2+deb8u2ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libnetty-java",
            "binary_version": "1:4.0.34-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "netty",
        "purl": "pkg:deb/ubuntu/netty@1:4.0.34-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:4.0.34-1ubuntu0.1~esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:3.2.6.Final-2",
        "1:4.0.32-1",
        "1:4.0.33-1",
        "1:4.0.34-1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libnetty-java",
            "binary_version": "1:4.1.7-4ubuntu0.1+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "netty",
        "purl": "pkg:deb/ubuntu/netty@1:4.1.7-4ubuntu0.1+esm2?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:4.1.7-4ubuntu0.1+esm2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:4.1.7-4",
        "1:4.1.7-4ubuntu0.1~esm1",
        "1:4.1.7-4ubuntu0.1",
        "1:4.1.7-4ubuntu0.1+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libnetty-java",
            "binary_version": "1:4.1.45-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "netty",
        "purl": "pkg:deb/ubuntu/netty@1:4.1.45-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:4.1.45-1ubuntu0.1~esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:4.1.33-1",
        "1:4.1.33-2",
        "1:4.1.33-3",
        "1:4.1.45-1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libnetty-java",
            "binary_version": "1:4.1.48-4+deb11u1build0.22.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "netty",
        "purl": "pkg:deb/ubuntu/netty@1:4.1.48-4+deb11u1build0.22.04.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:4.1.48-4+deb11u1build0.22.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:4.1.48-4"
      ]
    }
  ],
  "aliases": [],
  "details": "Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers \u0026 clients. In Netty (io.netty:netty-codec-http2) before version 4.1.61.Final there is a vulnerability that enables request smuggling. The content-length header is not correctly validated if the request only uses a single Http2HeaderFrame with the endStream set to to true. This could lead to request smuggling if the request is proxied to a remote peer and translated to HTTP/1.1. This is a followup of GHSA-wm47-8v5p-wjpj/CVE-2021-21295 which did miss to fix this one case. This was fixed as part of 4.1.61.Final.",
  "id": "UBUNTU-CVE-2021-21409",
  "modified": "2026-06-08T16:09:12Z",
  "published": "2021-03-30T15:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-21409"
    },
    {
      "type": "REPORT",
      "url": "https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21295"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/netty/netty/commit/b0fa4d5aab4215f3c22ce6123dd8dd5f38dc0432"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/netty/netty/security/advisories/GHSA-f256-j965-7f32"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/netty/netty/security/advisories/GHSA-wm47-8v5p-wjpj"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-6049-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-21409"
    }
  ],
  "related": [
    "USN-6049-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-21409"
  ]
}



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